Wheat (Triticum aestivum L. cv. HD 2285) was grown in control (C) and heated (H) open top chambers (OTCs) for entire period of growth and development till maturity. The mean maximum temperature of the entire period was 3 ºC higher in H-compared to C-OTCs. Net photosynthetic rate (P N ) measured at different temperature (20−40 ºC) of C-and H-grown plants showed greater sensitivity to high temperature in H-plants. P N measured at respective growth temperature was lower in H-compared to C-plants. The CO 2 and irradiance response curves of photosynthesis also showed lesser response in H-compared to C-plants. The initial slope of P N versus internal CO 2 concentration (P N /C i ) curve was lower in H-than C-plants indicating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) limitation. In irradiance response curve, the plateau was lower in H-compared to C-plants which is interpreted as RuBPCO limitation. RuBPCO content in the leaves of C-and H-plants, however, was not significantly different. Ribulose-1,5-bisphosphate carboxylase (RuBPC) initial activity was lower in H-plants, whereas activity of fully activated enzyme was not affected, indicating a decrease in activation state of the enzyme. This was further substantiated by the observed decrease in RuBPCO activase activity in H-compared to C-plants. RuBPCO activase was thus sensitive even to moderate heat stress. The decrease in P N under moderate heat stress was mainly due to a decrease in activation state of RuBPCO catalysed by RuBPCO activase.Additional key words: CO 2 and irradiance response curves; internal CO 2 concentration; ribulose-1,5-bisphosphate carboxylase/ oxygenase (RuBPCO) content and activation state; RuBPCO activase.

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Cauliflower is grown in all the agro climatic zones of India, accounting for an area of 3.9 lakh hectares with production of 73.4 lakh tones. Hence, studies are to be undertaken to identify genotype and analyze the physical characteristics among the cultivated genotypes (Namdhari Seeds 60 N, Namdhari Seeds 133, Pusa Meghna and Basant) grown under hills and plains of Kerala, India. In this study, significant differences were observed in yield of cauliflower which ranged from 21 – 26.4 kg /16 m2 in hills and 0.78 – 1.43 kg /16 m2 in plains. Among the cauliflower genotypes, NS 133 was found to be the best for hilly region in early yield and yield attributes. The cauliflower genotype NS 133 exhibited better performance in hills in terms of high curd yield (26.4 Kg /16 m2), curd weight (800 g) and curd height (13.93 cm). In general, harvest maturity was delayed by 39 – 45 days in the plains as compared to higher altitudes. The cauliflower genotypes which exhibited superior performance in hills and plains were selected for further sensory evaluation studies. In this study cauliflower genotype NS 60N recorded superior organoleptic qualities when grown in plains than hilly region. However in the case of genotype NS 133, the differences in sensory qualities between produce from hills and plains were not significant.

Abstract:The present study was undertaken to identify the superior cabbage genotype and to examine their physical yield performance among the four cultivated genotypes namely Namdhari Seeds 183, Namdhari Seeds 160, Namdhari Seeds 35 and Tropical Sun Plus, grown in plains and higher altitude of Kerala. Study revealed that significant differences were observed in yield levels of cabbage and it was ranged from 22.6 -29.3 kg /16m 2 in hills and 1.27 -22.06 kg /16m 2 in plains. Among the cabbage genotypes, NS 183 was found to be the best for hilly region in terms of higher head yield (22.06 Kg /16m2 ), head weight (729.6 g), head height (11.1 cm) and early maturity. Similarly, Tropical Sun Plus exhibited better performance in plains in terms of higher head yield (22.06 Kg /16m2), head weight (729.6 g) and head height (11.1 cm). The individual genotype which exhibited the superior performance in hills and plains were selected and compared for the general biochemical characters like Moisture content, acidity, ascorbic acid, protein, phosphorus, calcium and potassium. Finally, the study found that, the genotype grown at hill (Tropical Sun Plus) was recorded a higher biochemical characters than genotype grown in plains (Tropical Sun plus). Similarly, hill grown genotype (NS 183) recorded a higher biochemical characters than the plains grown genotype (NS 183).

Passion fruit nectar was developed from yellow and purple passion fruit separately and also by blending both yellow and purple fruits, in different combinations of TSS and juice. It was initially subjected to organoleptic evaluation to determine the best combination of TSS and juice content in nectar. Organoleptic evaluation revealed that passion fruit nectar containing 20% juice and 20°Brix was more acceptable in all the three categories (yellow and purple separately, and yellow blended with purple). Total soluble solids, non-enzymatic browning, reducing, non-reducing and total sugars increased while, titratable acidity, vitamin C, total carotenoids, total phenols and total flavanoids decreased during storage. Organoleptic quality of passion fruit nectar declined during storage in all the treatments. The rate of decline was faster in nectar stored under ambient conditions compared to those stored under refrigerated condition. Microbial load in all the samples was within the acceptable limits even after three months of storage.