There is a limited genetic variability available in genetic resources of upland cotton (Gossypium hirsutum L.), which restricted the breeding activity. The objective of present study was evaluating the genetic variability in RIL population derived through intraspecific hybridization between RHAP 12 and RHAP 15 genotypes. The 222 RIL were evaluated during kharif 2018 at University of Agricultural Sciences Dharwad. The RILs were evaluated for agronomic and fibre quality traits such as plant height (cm), number of monopodial branches, number of sympodia branches, boll per plant, seed cotton yield per plant (g), seed Index (g), boll weight (g), lint index(g), ginning out turn (%), fiber strength (g/text), fiber length (mm), micronaire value (µg/inch), maturity coefficient (%), fiber elongation (%) and fiber uniformity ratio (%). The RIL were exhibited the large variation for seed cotton yield per plant i.e. PCV of 34.44 per cent and GCV of 28.05 per cent. Similarly number of bolls per plant also exhibited the high genetic variation with PCV and GCV of 28.26 and 21.34 per cent respectively. Even though after utilizing diverse parents in hybridization program observed the limited variability with respect to fibre quality traits. The high heritability and genetic advance over the mean registered in seed cotton yield per plant indicating that additive gene action. The desirable association with yield was found between number of bolls per plant, number of sympodia per plant, boll weight and maturity ratio. It is concluded that RIL population had high potential for enhancing the yield and fibre quality traits. K e y w o r d sCotton, Recombinant inbred lines (RIL), phenotypic (PCV) and genotypic (GCV) coefficient of variation

SUMMARY :Higher atmospheric CO 2 concentration may influence positively plant production.Carbon dioxide was substrate for photosynthesis and gradient increase between the ambient air and mesophyll cells. Plants respond not only to change in surrounding CO 2 concentration, but to modifications of their microenvironment. Plants with C 4 photosynthetic pathway showed negligible photosynthetic response to elevated CO 2 because the C 4 cycle increased the CO 2 concentration in bundle sheath cells to the point where very little photorespiration occurs and calvin cycle is nearly saturated with CO 2 However, there is no consensus on the quantitave effects of increased CO 2 on plant processes and growth because of differences in response at different stages of growth, species of crops and growth limiting environmental factors. The purpose of this paper was to study the biophysical response of maize genotypes to elevated carbon dioxide and temperature regimes. The exposure of the crop elevated CO 2 and temperature regime resulted in the significant decrease in the photosynthetic rates. The minimum reduction was observed in HTMR-1, HTMR-2 and NK 6240 and the maximum in ARJUN and 900M-GOLD. Among the genotypes NK 6240, HTMR-1 and 900 M-GOLD genotype recorded maximum transpiration rate and stomatal conductance whereas, the genotypes HTMR-2 and ARJUN had the least transpiration rate and stomatal conductance. More detailed investigations are needed to complete our imagination about future consequences of possible climate variations, mainly in local level.

ABSTRACT:The study was conducted in Uttara Kannada districts during the year 2012-2014. The study area lies between 13.92 o N to 15.52 o N latitude and 74.08 o E to 75.09 o E longitude with an area of 10,215 km2. The Indian satellite IRS P6 LISS-III imageries were used to classify the land use land cover classes with ground truth data collected with GPS through supervised classification in ERDAS software. The land use and land cover classes identified were dense forest, horticulture plantation, sparse forest, forest plantation, open land and agriculture land. The dense forest covered an area of 63.32 % (6468.70 sq km) followed by agriculture 12.88 % (1315.31 sq. km), sparse forest 10.59 % (1081.37 sq. km), open land 6.09 % (622.37 sq. km), horticulture plantation and least was forest plantation (1.07 %). Settlement, stony land and water body together cover about 4.26 percent of the area. The study indicated that the aspect and altitude influenced the forest types and vegetation pattern. The NDVI map was prepared which indicated that healthy vegetation is represented by high NDVI values between 0.1 and 1. The non-vegetated features such as water bodies, settlement, and stony land indicated less than 0.1 values. The decrease in forest area in some places was due to anthropogenic activities. The thematic map of land use land cover classes was prepared using Arc GIS Software.

Climate change in terms of increase in atmospheric carbon dioxide and temperature has impact on agriculture including insect pests that minimize the crop yields. To address these impacts, biological studies on aphid, Aphis gossypii Glover on Bt cotton was conducted for six generations during 2013-14 and 2014-15 under different climate change conditions. The results revealed that the biometry of aphid was influenced by increased carbon dioxide (550 ppm CO2) and temperature (rise in 2°C of the prevailing temperature). This was evidenced by decrease in nymphal developmental time (3.67 ± 0.21 days), longevity of adult (9.43 ± 0.41 days), increased fecundity (32.46 ± 0.95) and reduced life cycle (12.28 ± 0.23 days) in the elevated conditions (both 550 ppm CO2 with 32°C as well as in 550 ppm CO2 + 34°C). However, morphometry of aphid showed slight variations in all the treatments but, aphids under elevated conditions showed reduced body size which indicated that the fitness of aphid was effected in the enriched carbon dioxide (CO2) and temperature conditions.

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