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Dr. Rajendra Prasad Central Agricultural University, Pusa

In the imperial Gazetteer of India 1878, Pusa was recorded as a government estate of about 1350 acres in Darbhanba. It was acquired by East India Company for running a stud farm to supply better breed of horses mainly for the army. Frequent incidence of glanders disease (swelling of glands), mostly affecting the valuable imported bloodstock made the civil veterinary department to shift the entire stock out of Pusa. A British tobacco concern Beg Sutherland & co. got the estate on lease but it also left in 1897 abandoning the government estate of Pusa. Lord Mayo, The Viceroy and Governor General, had been repeatedly trying to get through his proposal for setting up a directorate general of Agriculture that would take care of the soil and its productivity, formulate newer techniques of cultivation, improve the quality of seeds and livestock and also arrange for imparting agricultural education. The government of India had invited a British expert. Dr. J. A. Voelcker who had submitted as report on the development of Indian agriculture. As a follow-up action, three experts in different fields were appointed for the first time during 1885 to 1895 namely, agricultural chemist (Dr. J. W. Leafer), cryptogamic botanist (Dr. R. A. Butler) and entomologist (Dr. H. Maxwell Lefroy) with headquarters at Dehradun (U.P.) in the forest Research Institute complex. Surprisingly, until now Pusa, which was destined to become the centre of agricultural revolution in the country, was lying as before an abandoned government estate. In 1898. Lord Curzon took over as the viceroy. A widely traveled person and an administrator, he salvaged out the earlier proposal and got London’s approval for the appointment of the inspector General of Agriculture to which the first incumbent Mr. J. Mollison (Dy. Director of Agriculture, Bombay) joined in 1901 with headquarters at Nagpur The then government of Bengal had mooted in 1902 a proposal to the centre for setting up a model cattle farm for improving the dilapidated condition of the livestock at Pusa estate where plenty of land, water and feed would be available, and with Mr. Mollison’s support this was accepted in principle. Around Pusa, there were many British planters and also an indigo research centre Dalsing Sarai (near Pusa). Mr. Mollison’s visits to this mini British kingdom and his strong recommendations. In favour of Pusa as the most ideal place for the Bengal government project obviously caught the attention for the viceroy.

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20181
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Subject: Plant Physiology × Author: Neelambari × End date: 2023 ×
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    ThesisItemOpen Access
    Physiology of wheat (Triticum aestivum L.) under salt and high temperature stress condition
    (Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur (Bihar), 2018) Neelambari; Singh, Ajay Kumar
    Under natural conditions, plants are often subjected to a combination of different stresses such as salt stress and heat shock. Wheat crops are slightly salinity tolerant but as a cool season crop it is sensitive to heat stress at both vegetative and reproductive stages. Recent studies revealed that the response of plants to a combination of two different stresses is specific and cannot be deduced from the stresses applied individually because increased transpiration rate associated with high temperature stress worsen the harmful effects of salinity stress. Therefore, the present investigation entitled “Physiology of wheat (Triticum aestivum L.) under salt and high temperature stress condition” was conducted with three main objectives (1) Screening of wheat genotypes for combined salt and high temperature stress to identify the contrasting sets of wheat genotypes on the basis of physiological traits. (2) To study physiological and biochemical mechanisms of tolerance of wheat genotypes subjected to independent, and combined salt and high temperature stress conditions. (3) To quantify the changes in yield and yield attributes of wheat genotypes grown under independent, and combined salt and high temperature stress conditions. In the present study, two independent experiments were conducted. The first experiment was done in laboratory condition where 46 wheat genotypes were screened for individual and combined salinity and high temperature stress condition at seedling stage. Wheat seeds were sown in petri plate in three replications for germination. A saline solution of composition NaCl:CaCl2: Na2SO4 (7:2:1) with salinity levels at 4.0 and 8.0 dS m-1 were used as irrigation solution for giving salt stress treatments. High temperature treatment, was given by keeping the petri dishes in incubator at temperature 37 ± 2°C, and combined salinity and high temperature stress was given by transferring salinity stressed plant to incubator at high temperature (37 ± 2°C). The physiological parameters were measured in 10-day-old seedling. Physiological parameters (germination percentage, shoot length, seedling length, shoot fresh weight, root fresh weight, seedling fresh weight, root dry weight, shoot dry weight, seedling dry weight, vigour index I, vigour Index II and SPAD value) were measured and found to be reduced, except root length which was found to be increased in some genotypes and decreased in others under salinity, high temperature and combined stress. However the reduction was more pronounced under combined stress. On the basis of physiological data, the contrasting set of wheat genotypes (tolerant genotypes, i.e., KRL-1-4, KRL-19 and HD-2733, and susceptible genotypes, i.e., HT-8, HI-1563 and HD-2987) were identified for further study. The genotypes identified from screening experiment were used for a pot culture experiment to study the physiological and biochemical mechanism of stress tolerance and yield/yield associated parameters. Three replications of pot were arranged in factorial completely randomized design. Four treatments were given, i.e., control (wheat genotypes were sown timely in soil with ECe 1.3 dS m-1), salinity stress treatment (wheat genotypes were sown timely in natural saline soil with ECe 7.4 dS m-1), high temperature stress treatment (wheat genotypes were sown late in soil with ECe 1.3 dS m-1) and combined salinity and high temperature stress treatment (wheat genotypes were sown late in natural saline soil with ECe 7.4 dS m-1). The physiological and biochemical parameters were measured in flag leaf at anthesis period and yield parameters were measured at physiological maturity. The result revealed a decrease in physiological parameters in all wheat genotypes, while in tolerant group the decrease was less in all parameters, i.e., relative water content (25.0-29.6%), membrane stability index (23.9-27.2%), total chlorophyll (41.1-42.4%) and carotenoids content (14.9-17.2%), chlorophyll stability index (30.8-36.2%) and SPAD value (26.1-28.7%) as compared to susceptible group of genotypes in which percentage change in relative water content ranged from 37.7 to 41.2%, membrane stability index (37.9-44.5%), total chlorophyll (52.6-60.2%) and carotenoids content (15.1-33.9%), chlorophyll stability index (44.6-49.9%) and SPAD value (33.5-40.9%) under combined salinity and high temperature stress treatments. However, lipid peroxidation was increased in all the genotypes with minimum percentage increase in tolerant group which ranged from 58.6 to 60.3% and maximum percentage increase in susceptible group ranged from 71.4-88.3% under combined salinity and high temperature stress treatments. Greater antioxidant enzyme activities were induced in tolerant group, i.e., peroxidase (61.8-69.8%) and superoxide dismutase activity (75.4-86.9%). Similarly, proline content (61.1-68.1%), total phenol content (59.9-71.9%), total soluble sugar (42.5-48.9%), and free amino acids (43.3-50.9%) were higher in tolerant types, in comparison to susceptible group, i.e.,, peroxidase (40.6-49.2%), superoxide dismutase activity (50.7-56.3), total soluble protein (12.2-24.4%), proline content (37.6-47.4%), total phenol content (43.8-49.0%), and free amino acids (21.1-32.2%) under combined stress condition. However, total soluble protein content was found to be decreased less in tolerant group (19.6-21.6%) then in susceptible group (36.6-28.4%) under combined stress condition. Irrespective of the genotypes, combined stress reduced the yield and yield components in all genotypes. However, the reduction was minimum in tolerant genotypes, i.e., plant height (25.8-30.6%), number of grain per ear (28.6-34.1%), test weight (29.2-31.9%), harvest index (36.7-39.0%) and yield per plant (37.6-43.6%) as compared to susceptible genotypes in which reduction in plant height ranged from 36.9 to 49.6%, number of grain per ear 44.4 to 49.4%, test weight 38.7 to 43.4%, harvest index 47.3 to 50.3% and yield per plant 53.5 to 58.3% under combined stress treatments. However, floret sterility index was increased in all the genotypes with minimum percentage increase in tolerant group which ranged from 67.0-74.1% and maximum percentage increase in susceptible group ranged from 96.3 to 101.2% under combined salinity and high temperature stress treatments. From the present investigation it was evident that tolerant genotypes, i.e., KRL-19, KRL-1-4 and HD-2733 had the potential to cope up with the adverse effect of given stress treatments and they performed well under stress condition with least reduction in physiological, yield and yield associated parameters and greater increase in biochemical parameters. Among all parameters, antioxidants enzyme activity (SOD), phenol and proline content were highly correlated with yield per plant and showed maximum induction under combined salinity and high temperature stresses. Hence, the higher percentage increase in these parameters may be the reason for the tolerance of genotypes, HD-2733, KRL-19 and KRL-1-4. Possibly, some of these indices might prove useful for improving wheat genotypes to withstand combined salinity and high temperature.