Pacific Planters’

Digest

Combating Avocado

Pear Disease

RICH in Vitamin A (56.8 i.u. per ounce), the delectable avocado pear is among the most nutritious (and fattening) of Island fruits.

Some trials are currently being carried out in the Islands with the use of fungicides to control the pear’s most destructive disease, avocado foot rot (Phytophora root rot).

This disease, a fungus, can also affect many other crops including pineapples and papaws.

The fungus attacks the small feeder roots turning them black or brittle, and finally killing them.

Leaves of affected trees are smaller and paler than normal, often wilted and drop easily. Little, if any growth is produced, and, as the disease ad vances, the branches die back. The fruits are reduced in size and number. The fruit is not infected while on the tree, but this may occur if the fruit falls on infected soil.

Until fungicide trials have been completed, the best means of pre venting the spread of the fungus is by using clean and treated seed (place in a hot water bath at 120 to 130 deg. Fahr. for 30 minutes before planting), and also by grow ing seedlings in clean or fumigated soil. Trees should be planted in well drained areas, and not over-irrigated.

Mineral Supplements

LIVESTOCK which eat dirt, bones, wood and other assorted materials are in search of mineral elements lacking in their normal food intake.

This search-feeding has been noted in many areas of the world. No where is it more pronounced than in tropical regions where the absence or limited availability of elements is marked.

Deprivation of these necessary elements affect meat and milk pro duction, and when lacking in the extreme can result in death.

To determine what mineral ele ments are missing from stock diets, the ideal is, of course, a laboratory analysis of grass, grain, silage and all feed consumed. This is not always feasible, however, particularly in Island territories.

A quick way to overcome the

problem has been made with a com pletely new type of mineral supple ment now being introduced into Fiji, Samoa and the New Hebrides.

The minerals are being fed, each one separately (free choice) to stock in each of these areas. Stock will make their own selection, con centrating on that particular nutrient lacking, or not available, in sufficient quantity in normal pasture.

The advantage of free choice in take over the previous idea of holus bolus mixed mineral dosage is that, with the latter, stock receive elements already in ample quantities in the diet.

Excessive intake of any one mineral can complicate problems.

For example, feeding an excess of iron will tie up the phosphorus and produce iron rickets.

There are 13 assorted mineral supplements and they cover a wide range of necessary elements including phosphorus, iodine, magnesium, calcium, vitamin A, potassium and sulphur.

Weed Control In Papaws

WEED control between papaws has always presented difficulties.

Power-drawn or power-operated weeding implements leave strips along the sides of the rows which must continue to receive constant at tention with hand chipping.

Regular hand chipping is costly and time-consuming, hence weed control in papaws by chemicals has been investigated.

A large number of weedicides have been tested in established papaws at varying rates and times of applica tion. These include PCP, monuron, diuron, simazine, atrazine, SES, chloro-IPC, and dalapon.

With the exception of dalapon, all have been applied as pre-emergence sprays to initially weed-free, moist soil using from 120 to 200 gallons of water to the acre, depending upon soil moisture at the time of applica tion.

All of the pre-emergent weedicides tested have given reasonable control.

However, it was found monuron, diuron, atrazine and PCP gave best control, for periods varying from 11 to 18 weeks after application.

Interested growers wishing to try

either moruron, diuron or atrazine as pre-emergence sprays should apply the chemicals at the rate of 3 lb to the acre of the commercial product, calculated on the sprayed row area.

These materials should be applied as evenly distributed spray to weed free moist soil, using from 120 to 200 gallons of water.

The aim is to achieve even distri bution over the soil and, by holding the spray nozzle reasonably close to the ground, to avoid spray drift on to the foliage. Spraying should cease if weather conditions are found to be too windy.

In trials, dalapon produced a scorching and curling of the leaves of broad-leaved weeds but this was only temporary and the weeds soon recovered. On the other hand, it gave good control of grasses, particu larly when they were in active growth at the time of application.

If grasses are the problem, dalapon at 20 lb to the acre applied as a spray in a similar quantity of water should provide control.

Weedicides will have no adverse effect on the growth of the papaws if the chemicals are applied correctly.

Tonga Shows The Way

TONGA is currently setting a high standard in banana production which most South Pacific banana producing areas could well follow.

The kingdom has got down to tin tacks with its agriculture. An all out war on pests and diseases is being waged, and strict fertiliser programmes are being followed.

The old-time “ranching” method of banana planting is of the past.

Every available area of land is being utilised, and Tonga now insists that its growers follow correct planting methods.

Gratifying results are becoming more and more evident, and Tonga stands much to gain from its efforts.