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Tip Burn: Salt injury in Mango

The primary symptom of tipburn of mango leaves is necrotic sections around the leaf edges. It is important to figure out the cause of the condition in order to begin appropriate treatment. Tipburn of mango leaves is often, though not always, caused by one of three conditions.

a. The plant is not getting enough water

b. Salt has accumulated in the soil.

c. A magnesium deficiency is yet another possible cause of this problem.

All can occur at the same time, but either one can result in mango leaves with burnt tips. If you water your plant regularly, you are not likely to see tipburn of mango leaves caused by a moisture deficiency. Usually, sporadic irrigation or extreme fluctuations in soil moisture is the kind of cultural care that results in tipburn. Tipburn caused by fluctuations in moisture can be solved by regularizing irrigation. Set a schedule for watering your plant and stick to it.

Salt Injury: If your plant’s drainage is poor, salt can build up in the soil, causing tipburn of mango leaves. If salt has built up in the soil, try heavy watering to flush salts out from the root zone. If the soil has drainage issues, make drainage channels. Grow sunhemp as green manure crop as intercrop during rainy season and plough back at 50% flowering…This should be practiced atleast 4 to 5 years

Magnesium deficiency: use a foliar spray of compost tea (if organic farmer) potassium chloride KCl 2% (chemical farming). Repeat every two weeks.

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Centre seeks to ban 24 most harmful pesticides

The Union Ministry of Agriculture and Farmer’s Welfare in a draft May 14, 2020 notification proposed to ban monocrotophos, methomyl and carbofuran, three Class I pesticides associated with high levels of toxicity that resulted in farmers’ deaths.

Insecticides categorised Class I are extremely or highly hazardous for use. They contain ingredients that are extremely hazardous (Class Ia) or highly hazardous (Class Ib), as specified by the World Health Organisation.

“This is an important step. Class I pesticides like monocrotophos and carbofuran are highly toxic and heavily used in India. We hope the draft is notified without any dilutions,” said Amit Khurana, program director, Food Safety and Toxins, CSE.

The draft also proposed a ban on the use of 24 other pesticides that were being used for a long time in several parts of the country.

The notification is the culmination of a long-pending process that began with the setting up of the Anupam Varma committee in 2013 which reviewed the use of 66 pesticides that are used in India, but are banned in several other countries.  

In 2015, the Varma committee recommended a phased ban of 19 pesticides and recommended the review of 27 other pesticides.

A 2018 order from the ministry resulted in the ban of 18 pesticides, including seven Class I pesticides.

The new draft — based on the subsequent review of the 27 pesticides — said the ministry was satisfied that the use of these pesticides is likely to “involve risk to human being and animals as to render it expedient or necessary to take immediate action”.

Apart from those in Class I category, other pesticides were categorised as detrimental by the European Union prioritisation of endocrine-disrupting chemicals and are known to be disruptive for the body’s endocrine (hormone) system. These include insecticides such as chlorpyriphos, quinalphos, thiram and zineb.

These pesticides are banned in other countries, but are currently in use in India. The draft order pointed out alternatives that can be used instead of the pesticides.

Carbofuran, for instance, is banned in 63 countries including the United Kingdom (UK), those in the European Union (EU), Argentina, Canada, South Korea and New Zealand.

Similarly, monocrotophos is banned in 112 countries, including in the EU, UK, Brazil, China, Indonesia, Myanmar, Pakistan and Thailand.

Monocrotophos and acephate, another pesticide on the list of 27, were linked to the death of farmers in Maharashtra’s Vidharbha: In October 2017, 35 farmers died and hundreds of others were sick in Yavatmal, Nagpur, Akola and Amravati districts, after they inhaled the toxic pesticides that were sprayed on the fields.

There have been 18 Class 1 pesticides that were being used in India. If the draft becomes an order, 10 of these pesticides will be banned (three proposed and seven already banned in 2018).

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Locust Management

Once we have seen the locust outbreaks in the states of Madhya Pradesh and Rajasthan. Locusts are short horned grasshoppers which have swarming behavior. These insects are usually solitary, but under certain circumstances they become more abundant and change their behaviour and habits, becoming gragarious. Due to changing climate and the cropping practices, these have become serious problem in the last few years.

As the insects move in large groups, chemical pesticide sprays will not help. The recommendations made about Ulra High Concentration sprays (95% concentration against normal 5%) of Chemical Pesticides like Malathion (Hazardous), Chlorpyriphos (Highly hazardous) etc., are highly dangerous to environment as it increases pesticide load significantly that too in high concentrations. Many of these recommendations are based on the practices adopted in desert areas without human habitations or no water bodies whereas now we seeing these swarms in human habitations and if these same chemicals are sprayed the pesticide load increases significantly. This can also kill other non target, beneficial insects and distort the ecological balance and pose severe problem for the next crop season.

Insect Behavior

Locusts lays eggs in SANDY SOILS ONLY so the current swarm which was the result of eggs laid in middle east or in the desert areas of Pakistan or Rajasthan would be already 30 to 45 days old. they may live for another 30 to 35 days which essentially means till end of June Maximum. As they cannot lay eggs and hatch, we do not have fear of new outbreak.

Better Management Practices

Disrupt the development of the insects by cultivating the soil where eggs were laid

The best time to treat locusts is when they are in the ‘hopper’ stage, before they can fly. Programs to treat adult flying locusts are generally ineffective. Metarhizium anisopilae fungus to treat locusts is the safest and most effective way to mitigate the impact of locust damage. The fungal spores in the Metarhizium cause an infection inside the locust’s body which leads to death. A kill rate of 90% to 95% can be expected. This fungus multiplies and spreads from insect to insect and create better control.

As this mode of action is slower when compared to alternative chemicals such as organophosphates and synthetic pyrethroids (which stop feeding within a few hours, and kill locusts within two or three days), crops and pastures treated with this biological insecticde will remain at risk for longer. It can take up to 20 days to kill hoppers under cool conditions (10-14 days under warmer ideal conditions). Note that while it may take 10 – 20 days for the locusts to die, feeding may cease much earlier, so while treated hoppers may remain on crops, they may cause little damage.

Spraying Plant oils

There are experiments which proved that vegetable oils like neem oil, linseed oil etc (55%) can be sprayed by mixing with sodium bicarbonate solution (45%). This mixture showed more than 80% mortality when mixed with essential oils like clove oil, caraway oil, mint oil etc (1%) for further information

Spraying Soil Solution

Farmer Scientists like Venkat Reddy, Telangana was suggesting about using Soil solution to spray. The soil bacteria like Bt were found to be effective as contact killers against borers in the earlier season. This can be tried.