The architecture of leaves depend upon the light intensity available in the habitat in which they grow. The nature of cuticle, epidermis and the mesophyll including the amount of chloroplasts in them are designed based on the surrounding environment. Any imposed stress would have a direct effect on the leaf structure as they form the vital organs performing photosynthesis. The present study aims at comparing the effects of ultraviolet-B (UV-B) radiation on the foliar morphology, epidermis and the anatomy of three varieties of black gram (Vigna mungo (L.) Hepper) viz. Vamban-3, Nirmal-7 and T-9. Fully developed third trifoliate leaves from the top of 30 DAS (days after seed germination) black gram varieties under in situ supplementary UV-B radiation (2 hours daily @ 12.2 kJ m-2 d-1; ambient = 10 kJ m-2 d-1) were excised for assessment. UV-B stress induced changes in the leaf morphology and caused several injuries which were not recorded in normal plants. UV-B irradiated VAMBAN-3, NIRMAL-7 and T-9 produced very thick leaves. Thickness of cuticle, epidermis, leaf and mesophyll and volume of mesophyll increased in all varieties under UV-B exposure. The epidermis both on the adaxial as well as abaxial surfaces exhibited many changes after UV-B exposure. UV-B irradiated leaves developed many stomatal abnormalities. Abnormal stomata like, stomata with single guard cell, reduced size, malformations were more along with dead epidermal cells on the adaxial surface of UV-B irradiated plants. Such aberrations were absent in leaves under control conditions. The three varieties of black gram in response to ultraviolet-B irradiation modified the leaf architecture creating several barriers to combat the stress.
The present study aims at assessing the effects of ultraviolet-B (UV-B) radiation on the foliar morphology, epidermis and anatomy of three varieties of cowpeaviz. Gowmathi, Fola and NS-634. Fully developed third trifoliate leaves from the top of 30 DAS (days after seed germination) cowpea varieties under in situ supplementary UV-B radiation (2 hours daily @ 12.2 kJ m-2 d-1; ambient = 10 kJ m-2 d-1) were taken for assessment. UV-B induced changes were recorded in the leaf morphology, including injuries, which did not occur in normal plants. The epidermis both on the adaxial as well as abaxial surfaces exhibited many changes after UV-B exposure. Thickness of cuticle, epidermis, leaf and mesophyll and volume of mesophyll increased in all varieties of cowpea after UV-B irradiation. As a result, UV-B irradiated GOWMATHI, FOLA and NS-634 possessed very thick leaves. On prolonged exposure to UV-B, the leaves developed many stomatal abnormalities. Abnormal stomata viz., stomata with single guard cell, reduced size and contiguous stomata were more along with dead epidermal cells in UV-B irradiated plants on the adaxial leaf surface. Stomata were healthier in leaves grown under control conditions. From the results obtained, it is evident that cowpea varieties responded quickly to supplementary ultraviolet-B radiation by modifying the foliar anatomy to withstand the stress.
The green house gases accumulating around the earth due to human activity, increases in thickness day by day and the heat that normally would escape the troposphere and enter the stratosphere no longer does so, there by cooling the stratosphere. Cooler temperature favours depletion reaction in ozone layer, allowing enormous ultraviolet-B (UV-B) radiation into Earth’s surface, affecting the plants in the biosphere. The present study was carried out to compare the effects of ultraviolet-B (UV-B) radiation on the foliar morphology, epidermis and the anatomy of three varieties of green gramviz. CO-8, NVL-585 and VAMBAN-2. Fully developed third trifoliate leaves from the top of 30 DAS (days after seed germination) green gram varieties under in situ supplementary UV-B radiation (2 hours daily @ 12.2 kJ m-2 d-1; ambient = 10 kJ m-2 d-1) were excised for assessment. UV-B stress induced changes in the leaf morphology and caused serious injuries which were not recorded in normal plants. The adaxial and abaxial surfaces of epidermis exhibited several changes after UV-B exposure. On prolonged irradiation with UV-B, leaves exhibited various kinds of abnormalities. Due to UV-B irradiation CO-8, NVL-585 and VAMBAN-2developed very thick leaves. Thickness of cuticle, epidermis, leaf and mesophyll and volume of mesophyll enhanced in all varieties under UV-B exposure. UV-B irradiated leaves developed many stomatal abnormalities. Abnormal stomata like, stomata with single guard cell, reduced size and persistant stomatal initial were more along with dead epidermal cells on the adaxial surface of UV-B irradiated green gram crops. Such aberrations were absent in leaves of control crops. The leaves of green gram varieties developed structural barriers to screen UV-B radiation, by increasing cuticle thickness, epidermal layers, trichome frequency and volume of the internal organs, but reducing leaf size and area.
This paper examines the concerns and issues in agricultural finance in Andhra Pradesh. Agriculture in Andhra Pradesh, source of agriculture credit and types of agricultural schemes in Andhra Pradesh have discussed in this paper. The analysis states that the credit delivery to the agriculture sector continues to be in sufficient. In order to make it sufficient government of Andhra Pradesh is proposed to issue Rs. 69548.83 Crores towards Agriculture Credit for the year 2015-16. The Government of Andhra Pradesh has designed a strategy to transform the Agriculture and Allied sectors in Partnership with International Crops Research Institute (ICRISAT). This strategy will be operationalized in a phased manner setting the standards for a new development paradigm in tune with the change scenarios to enable Andhra Pradesh amongst the best three performing states in India by 2022.