Impact of Leaf Area Index on the Absorption of Photosynthetically Active Radiation in Barley (Hordeum vulgare L.) Crop under Diverse Sowing Dates and Cultivars
Mohit Godara *
Department of Agricultural Meteorology, CCS Haryana Agricultural University, Hisar-125004, India.
Surender Singh
Department of Agricultural Meteorology, CCS Haryana Agricultural University, Hisar-125004, India.
Chander Shekhar Dagar
Department of Agricultural Meteorology, CCS Haryana Agricultural University, Hisar-125004, India.
Anil Kumar
Department of Agricultural Meteorology, CCS Haryana Agricultural University, Hisar-125004, India.
Ankit Yadav
Department of Climate Change & Agricultural Meteorology, Punjab Agricultural University, Ludhiana, Punjab-141004, India.
Neeraj
Department of Agronomy, CCS Haryana Agricultural University, Hisar-125004, India.
*Author to whom correspondence should be addressed.
Abstract
Photosynthetically Active Radiation (PAR) is crucial for the physiological development of crops as it plays a key role in photosynthesis. A study was conducted at the CCS HAU Research Farm in Hisar, Haryana, during the rabi season of 2022-23 using a Split-plot design to explore the effect of Leaf Area Index (LAI) on absorbed PAR under different sowing dates and most commonly grown varieties of the region. Four barley cultivars (V1-BH 393, V2-BH 902, V3-BH 946, and V4-BH 885) were selected and grown under different sowing dates (D1 - 9th November 2022, D2 - 24th November 2022, D3 - 9th December 2022, D4 - 24th December 2022). The LAI and absorbed PAR were measured based on field observations. The findings indicated that the timely sown crop (D1) absorbed the highest PAR (86 to 95 %) and decreased absorption as sowing was delayed with the last date of sowing only absorbing 83 to 93 % of incoming PAR. D1 had more PAR absorption and LAI leading to more photosynthate accumulation and enhanced dry matter accumulation and an enlarged grain-filling period. The cultivar BH 885 absorbed more PAR followed by BH 946, BH 902 and BH 393. The results showed a clear and strong positive correlation between LAI and absorbed PAR in all the treatments. Thus, early sowing dates and BH 885 variety is recommended for semi-arid climate of Hisar region in western Haryana.
Keywords: Barley crop, leaf area index, absorbed PAR, sowing dates and cultivars