Role of boric acid on economic seed production of alfalfa under climatic conditions of Sargodha

Abstract

Alfalfa is one of the most important forage crops worldwide because of its wide range of adaptability and good forage quality. Seed yield is generally considered to be of secondary importance and is characterized by often poor seed yield and seed quality. A field experiment was conducted to determine the impact of boric acid foliar applications along with a basal dose during anthesis to enhance the alfalfa seed yield in agro-ecological conditions of Sargodha.  In foliar boric acid fertilization 0, 2, 4, 6, 8, 10 boric acid along with basal dose 23-80-50 (NPK kg ha^-1) was used. Phosphorous and potash were applied at the time of sowing while nitrogen will be applied in two split doses; half at sowing time and half of 1st irrigation. Two foliar applications, 1^st at intensive plant growth stage and the 2^ndat the beginning of the blossoming of the crop.  The concentration of boric acid solutions used were  2 ,4 , 6  ,8 and 10 glit^-1  which produces a seed yield of 161.7, 167.9,171.3, 175.0,186.7 and 176.1 kg ha^-1 in year 2015-16 while  next year in 2016-17 produces a seed yield of 286.5, 299.2,304.6, 308.3, 312.1 and 310.1kg ha^-1 respectively which is higher than year 2015-16. Foliar fertilization with boron influenced forming of slightly higher number of seeds in the pod. Boron influenced the average increase of yield, with a slightly greater difference compared to control. Number of seeds per pod in boric acid dose of 0, 2, 4, 6, 8 and 10 remained 6.1, 6.3, 6.4, 6.6, 6.8 and 6.7respectively in year 2016-17 which were higher than 4.3,4.4,4.5, 4.5,4.9 and 4.7  in year 2015-16. Overall 8 g liter^-1  boric acid foliar fertilization  produces 8.9 % higher seed yield, 11.4 % higher no of seeds per pod compared to control in the year 2016-17 while produces 15.4% higher seed yield and 13.9 % higher no of seeds per pod as compared to control in the year 2015-16.