Journal of Horticultural Sciences

R. M. Bhatt ¹, N. K. Srinivasa Rao ¹, A. D. D. V. S. Nageswara Rao ¹

Affiliations
1 Division of Plant Physiology and Biochemistry, ICAR-Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru - 560 089, IN

Abstract

A study was conducted to evaluate the effect of exogenous application of glycinebetaine (GB) on physiological response in hot-pepper (Capsicum annuum L. vs. Arka Lohit and Pusa Jwala) under water stress. Glycinebetaine was applied to seeds as well as plants through foliar applications. Water stress affected considerably the morphophysiological parameters in both the cultivars. However, in glycinebetaine (GB) treated plants, plant height, leaf area (LA), flower and fruit number and total dry matter (TDM) were greater compared to the untreated stress plants (T4) under water stress. Glycinebetaine application enhanced the photosynthesis (P_N) in water deficit experiencing plants, mostly due to a greater stomatal conductance (g_s) and carboxylation efficiency of CO₂ assimilation. In both the cultivars after 12 day of stress, the P_N decreased from 10.1 to 1.0-1.3 μ mol m^-2 s^-1 in untreated stressed plants (T4), while in the treated stressed plants P_N had reduced to 2.0 - 3.0 μ mol m^-2 s^-1 (T1 - T3). The application of GB increased the WUE in both the cultivars. The better WUE in treated plants of hot-pepper under stress was attributed to the improved P_N. The higher per plant yield in the GB applied plants under stress in both the cultivars associated with higher P_N rate, gs and WUE in treated plants. Though there was an increase in P_N rate, WUE and plant yield in the treated plants (T1 - T3), the better results were found in the plants (T2) where seeds were treated and foliar application was given at the time of imposing stress.

Keywords

Glycinebetaine, Hot Pepper, Photosynthesis, Stomatal Conductance.

Full Text

   

R. M. Bhatt ¹, Rashmi ¹, A. D. D. V. S. Nageswara Rao ¹, R. H. Laxman ¹, T. H. Singh ¹

Affiliations
1 Division of Plant Physiology and Biochemistry, Indian Institute of Horticultural Research, Hessaraghatta lake Post, Bangalore - 560 089, IN

Abstract

A study on seed germination and seedling growth was conducted with five cultivars of Solanum melongena L. (cvs. Arka Nidhi, B.P.L.H.-1, Arka Neelakanth, Arka Keshav and Mattu Gulla) and a wild species Solanum macrocarpon L. under different levels of osmotic potential induced by polyethylene glycol (PEG 8000). Germination declined progressively in response to decreasing (more negative) water potential, and no germination was found beyond - 0.4MPa in any of the cultivars/species. Except for cvs. Arka Nidhi, B.P.L.H.-1 and Mattu Gulla, no germination was seen at -0.4MPa Cultivar Arka Neelkanth failed to germinate under any of the osmotic concentrations tested. Response in term of ischolar_main growth was better in Arka Neelkanth, followed by Arka Nidhi and B.P.L.H.-1, upto transfer from different levels of osmotic potential to Control (0MPa). Germination of primed seeds within 24h indicates that many processes leading to normal germination would have been completed during the priming process itself. In contrast to germination, growth extension in radicle was less sensitive to water stress.

Keywords

Brinjal, Germination, Osmotic Potential, Water Stress.

Full Text

   

J. Satisha ¹, G. S. Prakash ², R. M. Bhatt ³, P. Sampathkumar ²

Affiliations
1 National Research Centre for Grapes, P.B. # 3, Manjari Farm, Solapur Road Pune – 412 307, IN
2 Division of Fruit Crops, Indian Institute of Horticultural Research, Bangalore - 560 089, IN
3 Division of Plant Physiology and Biochemistry, Indian Institute of Horticultural Research, Bangalore - 560 089, IN

Abstract

Four varieties of grape namely Flame Seedless, Thompson Seedless, Sharad Seedless and Tas-A-Ganesh were subjected to different levels of moisture stress to study their physiological response. Stress was imposed for 14 days by withholding irrigation. Observations on relative water content, leaf water potential, leaf osmotic potential and gas exchange parameters like photosynthetic rate, transpiration rate, stomatal conductance and water use efficiency (WUE) were recorded. None of the varieties could survive for 14 days without irrigation (100% stress). Flame Seedless and Thompson Seedless at 50% moisture stress maintained higher turgidity as indicated by lesser reduction in relative water content and water potential attributed to better osmotic adjustment. Marginal reduction in photosynthesis and greater reduction in transpiration rate in the variety Flame Seedless may have resulted in higher WUE under moisture stress. Higher photosynthetic rate, lower transpiration rate, higher water relation parameters and high WUE in Flame Seedless under soil moisture stress indicated its better tolerance to drought.

Keywords

Grape Varieties, Soil Moisture Stress, Water Potential, Water Use Efficiency.

Full Text

   

C. Susmita ¹, T. S. Aghora ¹, N. Mohan ¹, R. M. Bhatt ²

Affiliations
1 Division of vegetable crops, ICAR-Indian Institute of Horticultural Research, Bengaluru - 560 089, IN
2 Divison of Plant Physiology and Biochemisrty, ICAR-Indian Institute of Horticultural Research, Bengaluru - 560 089, IN

Abstract

The present investigation is aimed towards breeding varieties of garden pea for early summer cultivation (March-May) that can tolerate temperatures up to 350C. High temperature tolerant accessions KTP-4, Arka Sampoorna, Oregon Sugar, Magadi local were crossed with Arka Ajit, Arka Pramodh, Arka Priya having superior pod quality, yield and followed by pedigree method of breeding, superior transgressive segregants from these crosses were advanced up to F7 generation. In F7, six selected advanced breeding lines were assessed for their performance in the field with checks during early summer for four years in succession. Results revealed significant differences between selected lines and checks wherein all the lines surpassed checks with yield ranging from 5.9-7.6 t/ ha and in checks it was only 2.6-3.1 t/ha. Among these six breeding lines, three lines were selected based on high yield (6.7-7.6 t/ha), pod quality characters and identified to be highly suitable for early summer cultivation.

Keywords

Breeding, Early Summer, Garden Pea, High Temperature, Stress Tolerance.

Full Text