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In the Western world, Goji berries (Lycium barbarum) are one of the latest fruits to have medicinal claims made for them.  However, these 15-25 mm long red berries have been part of the Chinese herbal medicine for centuries.  Traditionally they have been used to treat inflammation, skin irritation, nose bleeds, aches, pains and as a sedative. They are also commonly used with other botanicals in Chinese medicine for poor vision, anemia, cough and for treating infertility.

Note on nomenclature

Lycium barbarum is known as wolfberries in China and the United States, and as goji berries in Tibet and Mongolia.  Lycium chinense, L. europeaum and Fructus barbarum are synonyms for L. barbarum.  They belong to the Solanaceae family.  They grow wild in these countries but are also cultivated in China.  Bernard King has tasted both the Chinese and Tibetan varieties and much prefers the Tibetan or Mongolian.  He gave me a sample of dried Tibetan goji berries.  They were delicious with a cranberry/sultana like taste.  Highly recommended.  In Tibet, the berries are never touched by hand as they will oxidize and turn black if touched while fresh.  They are shaken onto mats, then dried in the shade.

A note of caution.  It has been made known to me that a related species, Lycium ferocissimum (buckthorn) can be a weed in parts of New Zealand.  Entry of Lycium ferocissimum, Lycium tenuispinosum and Lycium chilense into New Zealand is prohibited.

Medicinal value

 Claims are being made that eating them promotes long life, and in elderly people  increases the effectiveness of the immune system, increases appetite and improves sleep.  Most of the above claims are not backed by peer reviewed medical research.  Yet there are some studies indicating that extracts of goji berries may hold promise in some medical conditions (see below).  Dr Earl Mindell is a driving force behind Western interest in the medical properties of goji berries, particularly their anti-ageing properties, after observing the age of Tibetans and the use of goji berries in their diet.  However, dietary calorie restriction is also likely to a factor in Tibetan diets and are known to increase lifespan, so what are the critical factor(s)?  This is where epidemiological research is essential to determine which factor(s) best correlate with the life span.

Quackwatch (a website set up to assess medical claims) is critical of Dr Mindell, and indicates a number of important errors in his previous published work on herbal medicines.  It states that Mindell claims to hold valid credentials in nutrition. Although he does have a bachelor’s degree in pharmacy from the University of North Dakota, his Ph.D. is from the University of Beverly Hills, an unaccredited school which lacks a campus or laboratory facilities.  The Quackwatch review was written by Dr. Tyler, the Lilly distinguished professor of pharmacognosy (the science of medicines from natural sources) at Purdue University.  On checking the medical literature, I have been unable to confirm claims that goji berries increase immune function in humans (there have been studies on mice using intravenous injections), or stimulate growth hormone release (the so-called “youth hormone”).

On the other hand, one human study has indicated that eating goji berries (50 g per day of dried berries for 10 days) increases levels of an enzyme (superoxide dismutase) which is involved in reducing free radicals in the body, and decreases lipid (fat) oxidation products.  These results are an indication that oxidative stress is reduced by goji berries – oxidative stress is strongly suspected of being involved in ageing and a number of other human diseases.  Another controlled study has shown a decrease in a number of minor symptoms of everyday living such as fatigue and sleeping problems (reviewed by D.S. Burke et al. Current Topics in Nutriceutical Research vol.3 pp. 259-266, 2005).

The Sloan-Kettering Cancer Center in New York summarizes the known medical properties of goji berries.  The bark and the berry contain betasitosterol which can prevent cholesterol absorption in the gastrointestinal tract. Lycium barbarum polysaccharide has been shown to inhibit the growth of leukemia HL-60 cells (a study using cell cultures).  One study reported that in 75 cancer patients, infusion into the blood stream of a combination of  immune stimulation and a  polysaccharide from goji berries improved regression of a number of cancers and improved remission. However, the treatment method used is not standard in Western medicine.  A cerebroside (a type of fatty compound found in the brain and elsewhere) extracted from Lycium barbarum may help protect the liver from damage.

Studies in animals and in human cell cultures indicate that extracts of goji berries have antioxidant activity, enhance growth of immune cells, decrease insulin resistance (improving diabetes), have anti-tumour activity, inhibit damage to the sperm, decrease blood pressure and can decrease damage from a protein thought to be a cause of Alzheimer’s disease.  Most of these studies have been to test the properties of a polysaccharide extracted from goji berries, but these studies do not indicate that eating goji berries will have the same effects.  One of the functions of the gut is to breakdown polysaccharides into sugars, so it is unlikely that the polysaccharide ever reaches the blood stream.  As well, absorption of large molecules such as polysaccharides from the gut into the blood stream is extremely limited.

Goji berries (as do blueberries and avocadoes) also contain zeaxanthin, required for good eye health (a lack of zeaxanthin and lutein are a cause of age-related macular degeneration resulting in blindness).   Claims have been made that they are highly nutritious, with large amounts of Vitamin C, b-carotene (converted to Vitamin A in the body), Vitamins B1, B6 and E, most amino acids required for protein synthesis, minerals, antioxidants (including anthocyanins and other flavonoids) and essential fatty acids.  Levels of these compounds in goji berries need to independently verified and compared with levels in other fruits, as most or all fruits contain antioxidants and other nutrients.  The nutrient and anti-oxidant content may be the most important property of goji berries.

There is much more work to be done before goji berries can be recommended for treating human diseases (so far there appear to be only 3 studies actually using humans).  Contraindicated for people on “blood-thinning” medication (warfarin).

Cultural conditions and availability of plants

Bernard King has Goji berry shrubs for sale (available also through Northern Branch NZTCA).  These are sourced from the Himalayas, either Tibetan or Mongolian (similar properties).  $10 per plant either direct from Bernard or from our branch, cheaper for bulk orders.  The goji berry shrub is a scrambling shrub 2 m high by 3 m, requiring support – perhaps similar to raspberries.  Grows fast with some berries possible in the second year and bearing heavily at 3-4 years.

Patrick Riddall at Awakeri in the Bay of Plenty initially germinated around 600 plants.  This winter he is putting in around 3 to 4 acres of goji berries.   Patrick has supplied the following cultural notes.

The goji bush is a very hardy plant that handles extremes in temperature and will survive just about anything.  Optimum growth is in deep well drained fertile soil in full sun, they go better in full sun than partial sun.  The only thing the Goji bush does not like is having it’s roots sitting in water.  The roots like going deep and do not make good pot plants.  They like regular watering for optimal growth although are very drought resistant once established.  When planting them try to plant them in places were they get frost as this sets the fruit sugars and makes for sweeter fruit (my aside: they will survive –15C; so perhaps fruit from these plants will not be as good in Auckland and north).  Very attractive to caterpillars.

Notes from Sheryl:  This article was taken from the TreeCropper June 2006 – the newsletter of the New Zealand Tree Crops Association www.treecrops.org.nz  A copy is available in our library – kindly donated by Merv Cooper.

The author Gordon Lees will be one of the keynote speakers at the 2007 TreeCrops conference 13th-15th April being held in New Zealand – the program looks exceptionally good. After doing a PhD on cheese bacteria in Melbourne, Gordon spent the next 30 years in the neuro-sciences working in medical institutes then spent the next 27 years at the University of Auckland in the Biochemistry Dept and later in the Depts. of Psychiatry and Pharmacology section of the medical school. He is now retired and is a Research Coordinator for the Tree Crops Association focusing on the medicinal properties of plants. We’re hoping to catch up with Gordon in New Zealand later in the year.

I recently attended the California Rare Fruit Growers meeting in Orange County, California where I got to taste fresh Goji berries. They were large, elongated orange berries – no sweetness in the ones I tried even though the books say they are. They were OK but I’d like to try other varieties. Michael Nave says that in the US they have random seedlings and there is a great deal of genetic diversity in the berries in China – it’s not clear what is being grown in the US. He has been growing goji berries from different sources and the quality of the fruit varies widely. Some are excellent and some are inedible. The dried fruit is promoted heavily on the internet and truth about the origin is often sacrificed in an attempt to get sales. Unfortunately even the alleged organic dried fruit from China is often laced with pesticides and colorants. Goji don’t like hot summers. Once they are established they can tolerate heat but the smaller plants don’t like it at all.

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Nitrogen fertiliser will burn away all your organic carbon in the soil so whenever you add nitrogen fertiliser in any form, you need to add a carbon source – either humic or fulvic acid, or compost at the same time – it helps to balance out – it doesn’t draw out nitrogen out of the soil. Nitrogen is a gas and you want to lock it up in the soil. Having a carbon source holds it into the soil. Just having pure ammonium or even pure fish fertiliser within a day or two, the nitrogen will just evaporate. I use foliar fertiliser in the main growing season when there’s new growth – it’s very weak – do it at regular fortnightly intervals. You’re building your brix levels up. You can feed the trees a lot more and by doing that and spraying small droplets over a leaf, it becomes rapidly absorbed into the tree within an hour or two and you can actually see changes in the plant within 4 hours. When they talk about flushing, it either means putting a lot of fertiliser and a lot of water to get that growth happening. If a tree is healthy it will ward off pests and diseases so keep fertilising small amounts which is better than large amounts as the plant can deal with it a lot better. Use stone mulch about 2½” thick white quartz $40.00 per tonne and paramagnetic basalt fines – $100.00 a tonne. Put the basalt fines down first and the quartz on top then compost around the outer ring of rocks – about 3-4 large shovels per tree and you can put it right up to the trunk. As the tree gets bigger, we can extend the ring of stone mulch. I set up a trial over about 20 different trees and I put a whole lot of different materials down as mulch: different rock sizes/particles, different wood mulches, straw, different types of sand then put the water on and let it sit for a day or two then came back and did the finger test and I was very surprised to see the difference – then when it rained, I did another finger test and its amazing how there’s such a big difference between the different types of mulches. The one that held the most amount of moisture was a combination of large 8ml quartz and very fine basalt rock. We expected other mulches to do a lot better but that one was the most effective for us. I’m an Arborist and can get wood mulch but found it broke down after a year and it had to be reapplied so putting down the stone, it didn’t break down. We found with a lot of other mulches in very dry conditions, it won’t allow penetration of a small shower of rain so if you have wood chips, it becomes a barrier so when the water rains on that spot, it will run off elsewhere. Straw mulch will soak up a lot of water but if you do the finger test, under the soil is still very dry. Some of the growth rates we’ve had by pushing the trees hard – we only had sticks when we started – no more than 300mm – and now after 3-4 months, they are up to chest height so we’re hoping that by the end of the season they will be pushing well over head height and fruiting 2-3kgs per tree so it really helps to do your fertigation through your lines and do foliar feeding. We use NTS products.  An Indian scientist I talked to spoke about having a lot of plant vigour – they believe more in pruning so they push their plants with as much fertiliser and water as possible then they’ll go through and prune very heavily so the plant doesn’t lose any vigour but it will shock the tree and it will then fruit very heavily.

Fertiliser:  With any crop it’s usually applied at the 1^st major flush and there’s usually a window of opportunity from flushing to flowering so during that time, try and push them as much as possible.

Ben grows Jujube at Owen which is on the edge of the desert about an hour north of Adelaide. He imported a lot of varieties from Roger Meyer in California. He thinks a lot of our trees up here in Qld are lacking nitrogen so if your leaves are turning slightly yellow but still have a green vein, then you’ll know to put nitrogen on or if your tree is just sitting there and not doing anything, then push it along with some fertiliser.

Article compiled by Sheryl Backhouse

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I was talking with Michael HindmarshSTFC, one of our members who’s a Vet down at Gerringong, south of Sydney about the Moringa as I’ve been wanting to do an article on this tree for a while so he sent me a note from the report he wrote while on a Churchill Fellowship to the UK & Europe in 1992 titled “The Biomanipulation of Blue-Green Algae” so those of you who have dams with this problem might like to have a chat with him. Ph: 02 4234 0281 He’s going to write an article on it for us. Michael studied Vet Science at Qld Uni between 1971-75. 

“The Horseradish Tree is being studied by Dr. Bill Grant and Mr. John Sutherland of the University of Leicester. A special role of this tree is growing in sewage wastes and producing seeds which can flocculate turbid water. John Sutherland is establishing pilot plants in Africa where landholders can grow the seeds then grind them to clean their water supplies. Bill has found a thousand fold reduction in bacteria from water samples treated with a meal from these seeds. Here is a new permaculture system capable of growing on sewage, producing pods for human consumption or a natural water flocculant.”

From the net: The idea of using moringa tree seeds to clear water came from the country of Sudan. The women there learned to use the seeds to clarify water from the muddy Nile River. The method works like this: When added to water, the crushed seeds attract particles of dirt that are floating in the water including certain disease organisms. The dirt attaches to the seeds and they fall together to the bottom of the jar. Then you pour off the good water to drink. However you must learn to follow all the steps carefully if you are going to clarify water with moringa seeds. The dirtier the water the more seeds you will need. After you have the correct number of seeds there are a number of steps including crushing the seeds, adding water to make a paste, shaking, straining, shaking again, and so on. If you don’t do all the steps you won’t have clean water. It’s been two hours since adding the seeds to the water and it’s clean. When people can’t boil dirty, polluted water, they can use moringa seeds.

George found the following from Aisha El-Awady:

The resilient, fast growing Moringa tree is packed with so many vitamins and nutrients and has such a high nutritional value that it has been rightly dubbed by some as the miracle tree. All parts of this scruffy looking tree are edible; the leaves can be eaten raw, cooked like spinach or made into a powder that can be added to sauces, soups or chowders. The new leaves have a tendency to appear towards the end of the dry season when few other sources of green leafy vegetables are available. The young, green pods can be eaten whole and are comparable in taste to asparagus. The older pods can be used for their seeds, which can be prepared as peas or roasted and eaten like peanuts. The flowers which bloom around 8 months after the tree is planted, can be eaten fried and have the taste and texture of mushrooms. In Hawaii, the flowers are used to make a tea that cures colds. In addition to this, the flowers are a year- round source of nectar and can be used by beekeepers. When the pods mature and turn brown, the seeds can be removed and pressed to extract high quality oil similar to olive oil rich in oleic acid (73%). The mature seed contains about 40% oil. The oil, which is known as Ben oil, can be used for cooking, lubrication, in soaps, lamps and perfumes. The oil was highly valued by ancient Greeks, Romans and Egyptians and was used in perfumes and for skin protection; it was also used in Europe in the 19th century for the same purpose and was imported from the West Indies. The taproot of young trees can be used to make a spice resembling horseradish when vinegar and salt are added to it. Not only is the Moringa oleifera tree extraordinary in that all parts of the tree are edible, but the most amazing aspect of the tree is its exceptionally high nutritional value. The leaves of the Moringa tree are an excellent source of vitamin A (four times the amount in carrots), the raw leaves are rich in vitamin C (seven times the amount in oranges), and they are also a good source of vitamin B and other minerals. The leaves are also an outstanding source of calcium (four times the amount in milk), protein (twice the amount in milk), and potassium (three time the amount in bananas). The content of iron is very good as well and the leaves have purportedly been used for treating anaemia in the Philippines. The content of amino acids such as methionine and cystine is also high. Carbohydrates, fats and phosphorous content are low making this one of the finest plant foods to be found.

Africa’s Solution to Malnutrition?      These qualities have made the Moringa oleifera tree a candidate in the fight against malnutrition. A group of health workers from the Church World Service have been utilizing this highly nutritious and fast growing tree as a means to cure and prevent malnutrition in infants, pregnant and lactating women as an alternative to the classic and expensive condiments usually used such as whole milk powder, sugar, vegetable oil, and sometimes peanut butter. It takes around ten days to see an improvement in malnourished infants when Moringa leaves are used whereas it takes months for recovery with conventional methods. According to Dr. Lowell Fuglie, the West Africa representative of the Church World Service who used the Moringa tree as a base for a nutrition program, “for a child aged 1-3, a 100 g serving of fresh cooked leaves would provide all his daily requirements of calcium, about 75% of his iron and half his protein needs, as well as important amounts of potassium, B vitamins, copper and all the essential amino acids. As little as 20 grams of leaves would provide a child with all the vitamins A and C he needs.”

“For pregnant and breast-feeding women, Moringa leaves and pods can do much to preserve the mother’s health and pass on strength to the fetus or nursing child. One 100 g portion of leaves could provide a woman with over a third of her daily need of calcium and give her important quantities of iron, protein, copper, sulfur and B-vitamins.”

 “One rounded tablespoon (8 g) of leaf powder will satisfy about 14% of the protein, 40% of the calcium, and 23% of the iron and nearly all the vitamin A needs for a child aged 1-3. Six rounded spoonfuls of leaf powder will satisfy nearly all of a woman’s daily iron and calcium needs during pregnancy and breast-feeding.”

Water Purification    The Moringa tree has other extraordinary qualities; the powder from ground Moringa seeds and the presscake left over from oil extraction have the ability to clear murky water as it acts as a coagulant which attaches to particulate matter and bacteria in the water and falls to the bottom of the container. The purified water can then be poured out and boiled. This method has been used for centuries domestically and has recently been tried commercially and was found to be equally efficient to, if not surpassing, alum which is usually used and at a fraction of the cost.

Practical Uses      The bark of the tree can be used to make mats or rope and in tanning hides. The gum from the cut tree trunks is used in calico printing and in some medicines. The wood can be used to make a blue dye and can also be used as firewood. The flowers and roots of Moringa trees contain a powerful antibiotic known as pterygospermin, which also has fungicidal properties. An effective plant growth hormone can be extracted from fresh leaves and has been found to increase crop yields by up to 25-30%, and the leaves can also be used as a green manure to enrich farmlands.

Mother’s Best Friend The family Moringaceae contains 14 species of Moringa trees. Moringa oleifera, is a drought tolerant tree, and is the best-known member of this family. It is native to sub-Himalayan regions of northern India and is distributed all over the world in tropics and sub tropics. Moringa stenopetala, which produces larger seed and leaves than M. oleifera, inhabits Ethiopia and northern Kenya. M. peregrina is native in Egypt, Sudan, and the Arabian Peninsula and as far north as the Dead Sea. M. ovalifolia is found in Angola and Namibia. The tree has many different names. It is called the drumstick tree in India due to the long pods, or the horseradish tree as the roots may be used to make a spice resembling horseradish. In some parts of the world it is known as ‘Mother’s best friend’. In Senegal, it is known as Nebeday, which means “Never Die,” because the tree is outstandingly hearty. It is also known as the Ben Oil tree; the Benzolive tree in Haiti; Marum in Thailand; Yoruba in Nigeria and Malunggay in the Philippines.                           www.islamonline.net/English/Science/2003/02/article06.shtml

Sources:  Sreenivasan, Jyotsna, 2000:The Drumstick Tree A Natural Multi-Vitamin.

NCCCUSA, 2000: Expedition to Distribute 20,000 Moringa Tree Seeds in Tanzania.

ECHO. Moringa, Nature’s Medicine Cabinet:  ECHO Moringa and Carotene.

ECHO. Effectiveness of a Moringa Seed Extract in Treating a Skin Infection.

Fuglie, Lowell. New Uses of Moringa Studied in Nicaragua. ECHO.

ECHO. The Moringa Tree, Moringa oleifera, is Called Mother’s Best Friend.

ECHO. Using Moringa on a Larger Scale;    Portalmarket, Moringa Tree Powder.

Gardner, Ellen, 2002: Moringa tree has many uses, From Food to Firewood. Yumasun.

Price, Martin L., 1985: Fruits & Others: Articles The Moringa Tree. Tropical-Seeds.

Willi says

She heard that it is rich in B17 which is believed by some to be an anti cancer nutrient. In Indonesia all  parts of the plant are always cooked. Its Indonesian names are Klentang or Kelor. It was used to make a soup with Chicken to help recovery from sickness. The ingredients were leaves, pods, flowers, tamarind & chicken. The fibres from the pods had to be removed from the broth after cooking.

Article compiled by Sheryl Backhouse

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ABSTRACT
Fruitspotting bugs are the major pests of avocados grown in Queensland, Australia.  They feed on the fruit, which usually cracks, resulting in significant losses.  Regular insecticide sprays are required to limit the damage.  Thin-skinned cultivars have traditionally been considered to be more susceptible to the bugs because feeding damage is expressed on the thin skins as severe cracks and craters.  The damage is thus more visible than it is in the thick-skinned cultivars, which often do not crack but form ‘blind stings’ that are easily  overlooked.  The bugs are difficult to detect in the trees and monitoring for their activity must be on the basis of damage to the fruit.  Data obtained from a sprayed commercial orchard and from an unsprayed experimental block indicate that fruitspotting bugs prefer the thin-skinned cultivars of Fuerte and Wurtz to the thick-skinned cultivars of Hass and Sharwil.  Pinkerton appears to be an exception for although it has a medium-thick skin, it was the first to be attacked, possibly because it set fruit earliest, and the damage inflicted was severe.  In the sprayed commercial orchard, damage to Fuerte (1.9%) and Wurtz (4.3%) was significantly higher than that recorded on Hass (0.04%) and Sharwil (0.03%).  In the unsprayed block, damage was 68.5% on Pinkerton, 73.6% on Fuerte and 18.9% on Hass.  In orchards that consist of mixed plantings that include Fuerte, Wurtz or Pinkerton, these cultivars can be used as indicator trees for monitoring fruitspotting bug activity and also as decoy trees for targeted control.

INTRODUCTION Fruit spotting bugs cause serious damage to most tree fruit and nut crops grown on the east coast of Australia (Waite, 1990).

They breed on many native host plants as well as a wide selection of exotic ornamentals, from which the adult bugs migrate into orchards throughout the fruiting season (Waite and Huwer, 1998).  The bugs are especially attracted to fruit just after it has set and damage at this stage usually results in the fruit falling from the tree.  Many crops including avocados, are susceptible from fruit set in spring through to fruit maturity in autumn.  Orchards in particularly susceptible locations, which are generally in proximity to rainforest breeding areas, require frequent sprays to prevent devastating damage.  Such sprays are usually of endosulfan, the use of which has been questioned on environmental grounds.  On the other hand synthetic pyrethroids, which provide excellent control of the bugs, may result in increased spraying of various types of insecticide because of the disruption of beneficial insects and mites with the resulting flare of secondary pests such as mites and scales.  Research is currently focused on an investigation of the fruitspotting bug hotspot phenomenon and whether such areas of an orchard can be used for targeted monitoring and control.  In conjunction with this the relative susceptibility of different avocado cultivars to fruitspotting bugs has been investigated with a view to growing the most susceptible cultivars as trap or decoy trees, so that the bugs can be destroyed with minimal effort and cost before they disperse throughout the orchard.

MATERIALS AND METHODS
Various known fruitspotting bug hosts were considered for assessment as possible trap trees for the purpose of monitoring and control.  The increasingly popular ornamental plant, orange jessamine, Murraya paniculata, is very attractive to both species of fruitspotting bug.  However, fruit needs to be present on the plants to attract bugs and individual plants fruit inconsistently.  Moreover, on the Sunshine Coast of Queensland at least, Murraya does not carry a significant fruit load after October and so, although it is very attractive to adult bugs in spring and may act as a local focal point for early season breeding, it does not attract bugs for the major part of the avocado season.  The most consistently attractive and convenient bug host would be an avocado cultivar that is more attractive to the bugs than are others, and in which the damage is easily detected as it is inflicted.  Fuerte is an obvious candidate for this role along with Pinkerton and Wurtz.  Fuerte trees were closely monitored in a commercial orchard at Woombye, and fruitspotting bug damage was compared with that on Hass, Wurtz and Sharwil.  At Maroochy Research Station Fuerte, Pinkerton and Hass were compared for the timing and intensity of fruitspotting bug attack.  The number of fruit that showed fruitspotting bug damage on datum trees was recorded.  On the final assessment date, the total number of fruit on the trees was counted, in addition to fruitspotting bug damaged fruit.

RESULTS AND DISCUSSION
At Woombye, observations of damage to the fruit indicated that Fuerte did indeed suffer much more damage than Sharwil or Hass, and although the damage was also easier to see on the thin skinned Fuerte, the difference was real and not just apparent.  Wurtz fruit tended not to show bug damage clearly, and it was manifest at harvest mostly as smooth dimples rather than the cracks or craters that develop in Fuerte.  A row of Wurtz trees immediately adjacent to a stand of wild guavas proved to be a major hotspot in this orchard.  Assessment at harvest showed that damage to Fuerte (1.9%) and Wurtz (4.3%) was significantly higher than that recorded on Hass (0.04%) and Sharwil (0.03%).  In the mixed, unsprayed orchard at Maroochy Research Station, Pinkerton was the first to set fruit and so was the first to be attacked by bugs.  Eight fruit on one of two Pinkerton trees were damaged on 8 October 2002.  This increased to 23 and then 32 over the next two weeks.  By 18 November the two Pinkerton trees had 102 damaged fruit while two Fuerte trees nearby had a total of 11 damaged fruit.  By then the Hass fruit was at a stage that was attractive to the bugs and 15 fruit were damaged on two trees adjacent to the Pinkerton trees.  As the season progressed, some of the damaged Pinkerton and Fuerte fruit developed anthracnose and fell, but it remained clear that both these cultivars suffered much greater and earlier damage from the bugs in October and November than did the other cultivars, and attack continued through January, February and March.  In contrast, damage on Hass did not increase significantly after the initial period of attack in November and December (Table1).  At final assessment, mean damage was 68.5% on Pinkerton, 73.6% on Fuerte and 18.9% on Hass.  Over the past decade, avocado growers in south east Queensland have tended to remove Fuerte from their orchards because of the amount of damage that was caused by fruitspotting bugs.  This damage resulted despite frequent applications of insecticidal sprays.  Since the bugs will attack all cultivars, the action of removing the most attractive cultivar merely removed the distraction that Fuerte trees formerly provided, allowing the bugs direct access to cultivars such as Hass, Sharwil and Wurtz.

CONCLUSIONS
These data support the proposition that rather than culling Fuerte trees from orchards because of their susceptibility to fruitspotting bugs, they should be retained precisely for that reason as indicator/ trap trees, and to act as a decoy for the pests to reduce the damage that might be inflicted on the more highly regarded cultivars.

Acknowledgements This project is supported by the Australian Avocado Growers’ Asscn and Hort Australia Ltd.

Sheryl:   Muriel and Ken are members of our club.

For Table 1 and References see:
http://www.avocadosource.com/WAC5/Papers/WAC5_p515.pdf, p518  24Jan 2013

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Sheryl   This is part of a talk given by Gavin to our group earlier in the year.
Pruning Gavin  We prune on a 15° angle in from the outside to the top – Christmas tree shape. Up north we do them vertical. Reason we do angle pruning here is because of the sun because we are further away from the equator and it lets in more light if we open them up. If you look inside the trees, you’ll see that we have stripped the leaves off on the old branches – we’ve just left the leaves on the outside. Just take off the ones in the shade on the inside of the tree. You need 80 leaves per piece of fruit as a rule of thumb. Any more than 80 just creates issues. You leave them on the outside to photosynthesis. They don’t do it in the north plus they would get sunburn up north if we did that. Down here ie our Rockhampton and Wamuran farms we strip the leaves by hand. We tried to do it with chemicals but it’s hit and miss but it would take off leaves you don’t want off so we do that when we prune in June and July. It lets more light and air in and is less place for disease to harbour. Sheryl  Which way do you strip? Gavin  From the outside in. Just wear cotton gloves. Sheryl  Do you take the leaves away? Gavin  No, we just leave them where they fall. They throw their leaves off by the tonne! They’re not a very good tree backyard tree from an aesthetic point of view – lots of leaves! You’ll notice we have a pretty clean environment under the trees. We use to throw all the grass clippings and mulch – nice organic matter which is good for the trees’ health however it breeds disease and because of our sprayers and we’re blowing air, it bounces off and throws all that disease back up into our tree so we now have a sterile environment. When we prune, we pull all the branches out but we don’t go through all the loose leaves. There are people who go through and rake and burn them and always have bare dirt but we don’t go to that extent. It’s pruned with secateurs and gets thrown into the centre of the rows then we run the slasher over it and it all stays out there because that’s where the roots are anyway. Five years ago we would have gone through and tip pruned and thinned them out whereas now we wait until winter to do that because we get a better crop from it. If you want to really prune a large tree right down, you can cut off half the tree one year and do the other half the year after. We prune June/July in winter. You can overprune mangoes – pruning knocks production around for that year so the less you do the better down here in SE Qld. Up in Nth Qld is different. We found that after harvest we’d go through and tip prune all the old flower panicles, stems etc. and tidy it all up and if that’s early enough and you get a reasonable run into winter, you’re probably OK but if your tree doesn’t flush back again and it only flushes again say end of March, you end up with a really weak flush. Sheryl  I notice you don’t cut out the centre.

Gavin  No. We use to do that but what we found was that it can get sunburn and it encourages regrowth all on the inside so you’re forever in there pulling that out as well. The concept is that at flowering the tree will look like a fishbowl – there will be leaves all around the outside and inside will be totally open other than branches. You don’t get a heck of a lot of mangoes on the top of a tree – most are on the side so as you can see the tops have flushed again.

To rejuvenate big trees From a structure perspective you can prune as hard as you like with a chainsaw and you won’t kill them and they’ll just flush out. Late summer (is good but it’s important when you cut them down that you paint the whole tree that is left with a water based white paint otherwise they’ll burn badly and they won’t recover. Also cut on an angle so water will run off. We keep all our trees down to a height that is manageable from the ground – usually a max of 4 mtrs so when there is fruit on it, the weight of the mangoes will put it down to 3 mtrs. We then use a 1½ mtr picking pole so all the fruit are picked from the ground. Member:  We were in Taiwan and their trees are only 2½ mtrs. Gavin  They grow differently to us. They bag all their fruit, thin it out so they get perfect fruit.

Member:  Custard Apples are grown the same – about 2½ mtrs.

Anthracnose: If you get this, we take the whole branch right back. Some growers in NSW go through once the crop sets and when it is duck egg or bigger, they’ll go through and take all the dead panicles off because they will mark your fruit but if you are paying someone, it’s an added expense.   That wood is as thick as your finger so if you take it back to 500mm from where it last branched, it will push the flower out of that hardwood.

Spacing  6 metre x 3 metres. In the tropics 8 x 4 metres and most growers go with 10 x 5 metres but they only get around 10-12 tonne per hectare.  We’ve gone high density and keep the tree shape down. We can get 20-24 tonne to the hectare.

Foliar Fertiliser  We do this when the tree is flowering. Vic  The Brisbane Organic Growers were asking a question in their newsletter about putting foliar sprays on trees. Is it absorbed more by the top of the leaf or the underside?

Gavin  It depends on what you are trying to do. If you are trying to get something into the leaf like nutrients it takes in very little on older leaves so it doesn’t matter. You need younger leaves that are soft which allows it to go in. As to the top or the bottom, we try and get coverage on both because I think it does go through both however you’ll get 10 times as much in a younger lime colour leaf than you will on the dark green leaf. Our mister goes right through the tree as well as the top. It will depend on what sort of coverage we’re looking for. If we’re applying a foliar nutrient and we just want it on the outside, we’ll travel along at 6-7 km whereas if we want good penetration with a fungicide or insecticide, we’ll slow down to 3-4km an hour.

Soil Member  I notice you have sandy soil so obviously that controls your nutrient to your trees so you can control what goes into your trees a lot better than a backyarder on heavy soil. Gavin  Mangoes don’t need a specific soil to be good but the type of soil influences how you feed it. They will grow anywhere. The heavier soil takes longer to respond but doesn’t leach so if you put nutrients in there, it stays in there whereas in sandy loam that we have, we have to keep putting it in as it leaches so we put little bits in regularly. They are a relative of mangroves and in the Northern Territory and the Top End, trees will grow in water up to a foot deep for 3 months so they are tough. George?  On a heavy soil you would get more vegetative growth because it holds nitrogen better.

Gavin  Yes that is right. Ideally for mangoes, the harder country you put them on, the more fruit you will get off them. They are a very lazy tree commercially – they just want to keep growing vegetatively and there’s no money in mango leaves!  They don’t yield a lot compared to the amount of potential they’ve got with a big tree. The same size citrus will pull 40-50 tonne a hectare where the mango will have 8 tonne a hectare.

Gavin   In winter when you get a vegetative flush, we will use Mancozeb every two weeks in normal weather however if you get rain, you have to go back and put it on again. We also use it with a surfactant and it depends on whether we want to get coverage or penetration so if we are using a systemic fungicide eg Amastar that you wouldn’t be allowed to use. We use a systemic and with the Mancozeb we will use it with a bit of oil. We also use Copper and we’ll mix the two together. We don’t use Copper around flowering. It’s been proven safe but it can burn. Sometimes we use them separately but it depends on the season. When it’s been really dry, we’ll use Mancozeb then use Copper the next time but when it’s wet, we’ll mix the two together. Sheryl  When do you stop your spray program? Gavin   We don’t. We do it all year round. Whenever there is new growth, we’ll do it so while it’s flushing, you need to protect it about a month apart and then when it hardens off and if it hasn’t rained but if it rains we’ll still do it every two weeks and when it gets to flowering, that’s when it really cranks up and we’ll spray every 7 days regardless due to the dew factor. Dew is a big issue for us. You can use any type of copper depending on how much you want to spend. Cupric hydroxide is one of the better ones as it has a finer particle – the finer the particle, the better it will work but it’s more expensive so commercially we top end of the range so even in your backyard, I would use the top one as well. In this environment you need the best. Two things will kill the flower – Anthracose if it rains before it got to a stage before it could pollinate or it’s been too cold so there is nothing to pollinate or the stomata is not open because it’s too cold. George  You’ve probably heard about Peter Young’s boron recipe on the flowers. If your tree doesn’t have enough boron or not enough calcium, you’ll probably find you won’t get as good a fruit set as you should.

Gavin   We spray the flowers with fungicide obviously but nutritionally we put boron, zinc and iron twice during panicle extension. When they are about 6ins out, we’ll put a foliar boron, zinc and iron on. It will cost a bit more but we use a chelated form because we can mix them all together and we don’t need to go through as often. Boron is critical for opening the flower seed. With mangoes it’s easy to get boron toxicity so don’t go overboard on it. If we get a lot of rain, we won’t go through and refertilise. The rule of thumb is that canopy size is a similar size to the roots. If you have a 3 mtr tall tree, the roots will be 3 mtrs down. We’ll put a kilo of fertiliser on after rain. Compaction is an issue for us here as well because we’re playing in the wet ie every time it rains, we need to go down and spray so the mangoes are growing on raised beds. We’ve done that deliberately to shed the water away from the roots.

Rootstocks
The mango industry has very little data on rootstocks. There hasn’t been a lot of work done on this. The industry was based around Kensington Pride or KP as we call it and up until 15 years ago, that was the only mango. There is some rootstock work being done in the industry now however KP is still the most common rootstock only because we know what it is. There are probably better ones out there but they are unproven. It costs us $80,000 a hectare to put mangoes in the ground so you want to know what you are going to get. 

Sheryl  How do they take off the husk commercially?
Gavin   They put them in a tumbler to get the flesh off them then spread them out on a black piece of plastic to dry them out for a couple of weeks then do it by hand. A pair of secateurs to take the end off then an oyster knife! Very time consuming.

Pollination We use European bee hives from a commercial apiarist. We also grow strawberries so the hives get shifted over to the strawberries so we get free pollination and he gets the honey! In the Northern Territory where we have 400 hectares of mangoes, you need a lot of hives and we need to bring bees in so it’s a commercial operation and we pay $28.00 a week per hive and we’ll have 2000 out during flowering and we do this for a month. When the bees are there, we can’t do any spraying until they are in bed and in the NT, that’s dusk and as soon as it’s light they are out so all our spraying is done in the dark. One of the issues with one of the properties in Katherine NT is that we are right up against 2000 hectares of watermelon and they need to be pollinated from April through October so they’re continually rotating the bees around. Bees will travel 8kms so we need to be mindful of them around vegetatively as we’ve taken out some of the hives with Fipronel which is lethal on ants and a bit spilt into a puddle and the bees came and drank from the puddle and took it back to the hive and nailed the hive. Sheryl  The native bee people say they pollinate mangoes. Do you use them? Gavin   There’s not many around and they are hard to manage. Any insect will pollinate mangoes as they are easy to pollinate particularly when it’s warm. The issue down here is the stomatas don’t open when it’s cold and mid July we will take off every flower because it’s too cool to pollinate properly. It takes about a month to prune then we’ll go back again middle of July and take off everything again. George  They use to say that nubbins were caused by low 6° C temperature killing off the embryo but what you are saying is that the bees aren’t pollinating below a certain temperature so what causes the nubbins? Is it the lack of pollination or the cold or both? I think they’ve said that the embryo dies but you could see that by cutting the flowers when they are very little and looking at it under a microscope and you should see whether the embryo has gone or not. It’s the 1st time I’ve heard that lack of pollination causes nubbins. Gavin  It’s the lack of pollination but it can be caused by both but we think it’s 10°C. Stomatas won’t open so they can’t pollinate even if something was there to pollinate them so if there are no insects and insects aren’t out at that temperature so basically it’s a lack of pollination that are causing the nubbins.  Barbara:  We had a talk by Don Batten and he spoke about flower initiation in the drop of temperature and he says he prunes in May and that flower initiation happens when it’s cold. Gavin:  I agree with the concept but there are many ways of doing something. We use to do a lot of things that we no longer do. If we had done it in May, what can happen is that it can have another flush after that – not a flower. It will either be vegetative or floral so if they go vegetative at the end of May you can be in trouble. You’re going to have to take it all off and start again. If it goes floral at the end of May, you’re still in trouble because it’s too early and they won’t set. There are a lot of insects around but they don’t get out of bed til its 18°C so both ways you lose out. We do it end of June or even July depending on the winter. If you get a warm

winter, you can do it earlier. The concept is sound – just the timing and we’re getting better results if we push it back to July.

Pests There’s Mango Leaf Scale that probably does the most damage. They’re little white specks and they will kill the leaves and the leaves go yellow where they are and in a month, the leaf will go dead. There are chemicals you can use but a vegetable oil is an appropriate way of handling Mango Scale. You need a fine mist and ideally some air as that is how commercial people spray mango. We throw the spray in front of the sprayer and use the air to spread it. It’s the uniformity of the coverage that is important – not the volume.

Flying Foxes:  They don’t like green mangoes so we don’t see them til we get some ripe fruit in the orchard ie just getting a bit of yellow tinge. In commercial orchards, we harvest just prior to that stage – what we call mature green. Control rats with bait. Lorikeets are also an issue with mangoes. In the NT we have a lot of problem with white cockatoos. They are very destructive. They don’t eat the fruit. What they do is land on a branch, and the fruit is on a panicle and they watch it drop on the ground then go to the next!!  When we are picking, we’ll continually cut a heap of fruit throughout the day to make sure that we are harvesting at correct maturity as we pick before they are ripe. It is difficult to tell what is mature and what is not because colour is not a good indicator. The best way to tell with most mango varieties is the smoothness of the skin. When you run your hand over immature fruit, it has little bumps like fine sandpaper but once that smooths out, it will be ready to pick. Also the shoulders at the top of the fruit will tend to puff up and the stem will be lower than the shoulders. The nose (bottom end of the fruit) as well will fill out but sometimes depending on the year. Usually you will only get one mango per panicle.

Fruit Spotting Bug:  It can attack green fruit and we monitor for that. We get it quite bad here around Nov-Dec – two months before harvest. George  Do you get any damage from the fruit spotting bug on the young growth of the vegetative growth? Gavin  We don’t have a major issue but as soon as there is a hot spot, we will spray and one of them is a natural pyrethrum but if they’re hiding behind a leaf, you won’t kill them. We also get a little caterpillar on the young growth that grows to 2cm long, brown and white and we get hot spots of them as well. George  I know they get phytophthora in mangoes in the north – do you get any here?

Gavin   No, it’s not a big issue. Mangoes are not resistant to phytophthora but they have a massive tolerance to phytophthora.

Mango Picker  We built the machine ourselves. We have two people walking along cutting the mangoes from the stem and it needs to go into the water within 3 secs of picking otherwise the sap could burn the skin of the mango. There is also another person on a platform on the machine. Mango sap is toxic and burns the skin so the water circulates around the machine and we have another person takes the stems off. We put a detergent in the water to stop the smearing. The tank on the machine holds 1500 litres of water. We made another machine out of a Nissan Patrol 4×4 ute because when it’s wet, we kept bogging the other one and this machine can run down the centre and have two people either side. After we bring them back to the shed, we wash them again and put a fungicide in the water. George  Does time of the day make much difference to the pressure of the sap?

Gavin   It does. The turga pressure in the fruit is higher in the morning than the afternoon. The pickers just have to be more careful in the morning.

Ripening Mangoes after picking  Try and find the coolest well ventilated place in the house until they colour up to what you would call ripe then put it in the fridge and if you’ve grown it correctly, they should keep for around 2 weeks. KPs will go mushy in the freezer but Honey Gold don’t – well – not as much! They’re not as good as fresh but they’re still a solid piece of fruit. Different people like them greener and others prefer them riper. Store at about 12°C for as long as you can but it will continue to ripen. When you ripen at this temp, it’s too cool for the sugars to come up. We don’t use the Brix meter on our mangoes but we do on Strawberries and Pineapples because they don’t ripen after harvest. Watermelon is another that doesn’t ripen after harvest. Brix is not an accurate measurement of eating flavour. If you get a mango perfectly ripe and measured the brix then, then it’s consistent and it should be 14 brix but by then it’s too late to do anything about it.

Water   On a drip feed.

Pineapples  They put Nemacur over them for nematodes and Phos Acid to control the phytophthora. There are certain types of nematodes that will get into mangoes. We can’t grow Pineapples without using Phos Acid for phytophthora whereas we don’t treat Mangoes for phytophthora or nematodes. We also get a big Tea Mosquito the size of a fruit spotting bug and they’ll mark the fruit. They leave a black mark on the fruit. We also have a problem with wood ducks in our strawberries. They just demolish them!

Pineapple  If you want to keep them longer, don’t snap the top off – cut it off and that way it acts as a plug and the shelf life won’t change. If you break it off, it will only last a few days. The pineapple top will store for 6-8 weeks before planting. 

Weeds  We mainly use glyphosate (roundup). We use a bit of Baster on woody weeds like vines. It’s important not to let your weeds go to seed. You can maintain it with very light doses of glyphosate but if you let it get knee high in seed, it’s hard work.

Mango Checklist

Fertilise after harvest We do a soil and leaf analysis immediately after harvest but for a backyard grower if you have a tree around 3 metres, spread approx. 800gms around the tree after harvest. Something like CK55. It is very important to fertilise at this time of year so you get them to flush before winter. We have all our fruit off by the end of February.

Prune in winter June/July.  Strip off all the old leaves in the centre leaving all the new ones on the outside. If you decide to do a hard prune, use a water based paint on all the branches and trunk.

Foliar Fertiliser when the flowers get to 100mm long with Boron and Zinc and about a month later when the flowers are fully opened and just prior to fruit set. We buy it in chelated (liquid) form which is more expensive but easier to spray.

Pests  We spray the fruit with Bugmaster (Carbaryl) to control the Fruit Spotting Bug. Check around November/December.

Diseases  We use Mancozeb every 2 weeks once flowering commences and we continue this until harvest. 

Propagation  Take your scionwood from the current year’s flush that has hardened off – best time is December and January. (SE Qld) There is a disease called Mango Malformation which is a type of Fusarium disease so if you were propagating, it is important to get the tree tested against this as it can lay dormant for many years.

There are around 800 commercial mango growers around Australia. They are even grown in Victoria along the Murray River and Renmark in South Australia.

Sheryl  Gavin was telling me that the Honey Gold variety they grow freezes quite well and doesn’t go mushy when dethawed. I tested it out recently as I still had some frozen and found that they were very acceptable so can recommend this method. Nice recipes here:  www.mangoes.net.au

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