Read more
Diploma Thesis from the year 2023 in the subject Biology - Genetics / Gene Technology, grade: 8.0, , language: English, abstract: Recently, a mini core panel of 98 genotypes representing the diversity of Indian rice germplasm was identified. This mini core is a very important resource that can be evaluated for specific traits of interest to identify superior genotypes that could be used as parents in breeding programmes. The present study was focused on a systematic evaluation of mini core rice collection along with a set of germplasm from the North Eastern Hill Region under cold stress with following specific objectives: To study and compare the effect of three dates of sowing (early, medium and late) on rice mini core collection with respect to yield contributing traits, to determine the trait that most affects yield under stress through path coefficient analysis, to study the effect of cold stress at booting stage on pollen and spikelet fertility under controlled low temperature conditions and to identify tolerant and susceptible genotypes.
Rice farming is the largest single use of land for producing food. Ninety percent of the rice is produced in Asia, and it totaled 696 million tons in 2010. Rice production is one of the most important economic activities on Earth. Only 7% of all rice production is exported from its country of origin.
Various abiotic stresses directly or indirectly affect the physiological status of rice and negatively alter its overall metabolism, often with impacts on grain yield. Cold stress is one of the abiotic stresses which are common problem of rice cultivation. Cold stress causes various injuries to rice seedlings in low-temperature and high-altitude areas and is therefore an important factor affecting rice production in such areas. Rice is a cold-sensitive plant that has its origin in tropical or subtropical areas, and cold damage can cause serious yield losses. Low temperature effects the rice cultivation mainly in two stages of development i.e., seedling and booting. In both of them, cold temperature has harmful effects on crop productivity, as in the first case the number of established plants is affected and in the booting stage pollen sterility can be induced by cold, decreasing the final number of grains.
