Wrong practices making apple orchards vulnerable to rampant diseases: Report

Several wrong orchard management practices by apple growers have been highlighted in the report prepared by the University and Forestry, Nauni, on the basis of the field visits by scientists in July.

According to report, the wrong practices, hot and humid weather and unusually wet conditions caused widespread and severe diseases in apple orchards this year.

The teams of scientists, which visited all major apple growing areas in the state following the reports of major fungal attack in July, found Alternaria leaf spot/blotch as the most dominant disease in most orchards.

The scientists found wrong orchard management practices in most of the orchards overwhelmed by the fungal disease. The major practices red-flagged by scientists include indiscriminate mixing of chemicals for foliar sprays, excessive sprays and not following the recommended duration for the sprays.

“Most people are mixing fungicide, nutrients and insecticide in foliar sprays. It’s not recommended by the university but most growers are still doing it. It reduces the efficacy and the growers do not get the desired results. It has to stop if we have to make our orchards less vulnerable to diseases,” said Usha Sharma, Senior Scientist, Krishi Vigyan Kendra (KVK), Shimla. She led one of the teams that visited the various apple belts in July.

Growers demands

Quality assurance for pesticides and imported planting material

Greater check on vendors to prevent sale of non-recommended pesticides

Insufficient supply of pesticides of recommended brands

Compatibility chart needed for chemicals in the spray schedule

Easy to understand spray schedule and mentioning of fungicides’ groups

“Excessive use of fungicide is another problem that is assuming alarming proportion. Growers are doing far more sprays than recommended by the university,” she said. “Also, the growers need to adhere to the recommended time frame for fungicide sprays. Growers are doing it even after 10 days. It should be done 18-21 days after the previous application. At times the gap could be reduced to 15 days, but there’s no need to reduce it any further,” she said.

Sharma further said that the preventive sprays of insecticide and acaricides for insect/mite management were further aggravating the problem. “The precautionary use of these chemicals kills friendly predators that keep mite, insects under control. And later when the mite attacks, it becomes extremely tough to control it,” she said, adding that the mite-infested orchard becomes vulnerable to the attack of fungal diseases as well.

The scientists also spotted the use of non-recommended pesticides such as Simodis, Zero Mite, Miravis, Duo, Zamir, Kanemite, etc., and spurious fungicides at some places. “The presence of spurious pesticides can’t be ruled out. It’s for the government to check the entry of spurious pesticides in the market,” said Sharma.

Incidentally, the growers raised concerns regarding the efficacy of the chemicals they had been using in front of several visiting teams. “Besides, the use of fertilisers should also be need-based,” she said.