Anomalous Weather Conditions, Not Shift Of Transplanting Date, Responsible For Low Paddy Yield: Varsity Experts 15-12-2018

By Punjab Agricultural University on 17 Dec 2018


A reduction in the yield of rice in 2018 as compared to previous year has been observed in the states of Punjab and Haryana, although this year’s yield is comparable to the yield of rice in 2016.

Experts at Punjab Agricultural University have investigated the factors responsible for lower yield and have come to the conclusion that the same can be attributed to weather vagaries observed during the kharif season; and the paddy transplanting date of June 20 has had no negative impact on yield. Investigations have revealed that Punjab received more rainfall in 2018 as compared to 2017. Ludhiana district recorded an average rainfall of 395 mm in the year 2017, where as in 2018 it was 843 mm. Due to increased rain, a greater cloud cover was observed throughout the state during the rice vegetative phase, as a result of which there was a reduction in the number of sunshine hours. This further led to a decrease in tillering. Lack of sunshine also impacted the plant height and decrease in the number of branches which was the direct cause of low yield.

The second main cause of yield reduction is heavy rain during the last week of September. Two heavy rainfalls on September 22 and 28 were recorded for the first time in 50 years. As a result, the average temperatures starting from this period right up to mid October remained 4-5 degree centigrade below normal. This led to an increase in the number of empty grains and late maturing. In additional to heavy rainfall, the crop was flattened by strong winds and hail at some places. While the day temperatures fell 4-5 degrees below normal, there was lesser variation (1-2 degrees) in the night temperatures, which resulted in decreased difference between day and night temperatures. These temperature differences led to reduced translocation to the grains, reduction in grain weight and consequently the grain yield.

The revision of transplanting date to 20th June is beneficial for water saving as well as productivity and it would be irrational to roll back the water saving intervention of 20th June as the transplanting start date. Agriculture in Punjab will be stabilized only if we can deploy all possible strategies to conserve water. Another point worth noting is that even in Muktsar where rice transplantation was allowed on 1st June, low yields have been recorded compared to last year. Similarly, Haryana too has recorded low paddy yield. Till November 30, Punjab and even Haryana where transplanting date was 10th June recorded a deficit of 2.48% in paddy yield. Experts reiterate that extending paddy transplant date to 20 June has no impact on yield; rather, it is a step to help regenerate the falling water table. 

Experts suggest that if the real reasons for lesser paddy yield this year, are ignored, it might lead to formulation of policies that could negatively impact water conservation interventions in the state which could be detrimental to sustained agricultural growth.