<div>Background: Horsegram is an important pulse crop grown as Rabi crop in Tamil Nadu. Kharif sown crop could not flowers may be because of more number of tendrils produced as compare to Rabi sown crop. Hence, an attempt was made to reduce the number of tendrils and induce flowering in horsegram during Kharif season by plant growth regulators.&nbsp; 
 
Methods: A field experiment was conducted to study the impact of plant growth regulators viz., salicylic acid (100 ppm), chlormequat chloride (CCC - 250 ppm), mepiquat chloride (250 ppm), tri iodo benzoic acid (TIBA - 200 ppm) and nitrobenzene (0.2%) on physiological traits and tendril growth associated with flowering in horsegram during Kharif. Different treatments were applied through foliar application at 25 Days after sowing.&nbsp; 
 
Result: Among the PGRs, foliar application of TIBA registered the lowest number of tendrils (2.3) followed by CCC (3.0) compared to other treatments. Higher root length of 16.8 cm and RWC of 82.3% was found in CCC treatment. CCC also registered the highest photosynthetic rate (27.15 &micro;mol m-2 s-1), transpiration rate (18.06 mmol m-2 s-1) and lowest leaf temperature (26&deg;C) compared to other treatments. The highest soluble protein content of 13.1 mg g-1 was also estimated in CCC treatment followed by mepiquat chloride (12.51 mg g-1). Sucrose phosphate synthase (SPS) activity did not show any significant difference between the treatments. Number of flowers buds formed per plant was zero and hence the flowering did not take place in any treatments. Among the plant growth regulators used, TIBA and CCC registered its positive action on reduced the number of tendrils and leaf temperature, but not enough to induce flowering under Kharif season.</div>

Impact of Exogenous Plant Growth Regulators on Physiological Traits, Tendril and Flowering in Horsegram (Macrotyloma uniflorum Lam) under Kharif Season&nbsp;

<div>Background: Horsegram is considered as poor man&rsquo;s crop and it has high nutritive value for human being. Apart from its photo and thermo sensitive in nature, formation of tendrils with excessive vegetative growth is major constraints and reason for poor yield. The tendrils act as sink and utilize photo-assimilates for its continuous growth. Hence, a strategy is required for reduction of vegetative growth and tendril formation for yield improvement. The current study is aimed to enhancement of yield in horsegram through physiological approach. 
 
Methods: An experiment was conducted to study the impact of plant growth regulators and nutrients viz., brassinolide (1 ppm), CCC (250 ppm), nutrient consortium (K2SO4 (0.5%) + MAP (0.5%) + FeSO4 (0.5%) + boric acid (0.3%) and TNAU Horsegram Wonder (1%) on growth, physiological traits and yield of horsegram&nbsp;(Macrotyloma uniflorum) variety Paiyur 2 under rainfed condition during 2018 - 2020. Plant growth regulators and nutrient consortium were used as foliar spray at flowering stage (50 days after sowing) under field condition. 
 
Result: TNAU Horsegram Wonder showed supremacy to enhance photosynthetic rate, SPAD value, soluble protein and yield compared to other treatments. Early flowering and reduced number of tendrils were observed in CCC nutrient consortium and TNAU Horsegram Wonder treatments. Foliar spray of 1% TNAU Horsegram Wonder recorded highest SPAD value of 22.8 which is on par with BL nutrient consortium. Highest photosynthetic rate of 16.94 &micro;mol m-2 s-1 and lowest number of tendrils (2.6) were registered by 1% TNAU Horsegram Wonder. Foliar application of TNAU Horsegram Wonder at flowering stage registered highest grain yield of 1090 kg ha-1 and increased yield of 23% over control with BC ratio of 2.24.</div>

<div>Impact of Foliar Spray of PGR Nutrient Consortium on Growth, Photosynthesis and Yield of Horsegram (Macrotyloma uniflorum Lam) under Rainfed Condition</div>