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Entry means from 88 trials of runner- and virginia-type peanuts ( Arachis hypogaea L.) conducted over 16 years and three locations in the state of Georgia with an irrigated and a non-irrigated test performed at each year-location combination were examined to determine the mean performance for cultivars and breeding lines and to determine if they exhibit interaction with water regimes. All lines responded positively to irrigation for pod yield, total sound mature kernels (TSMK), 100-seed weight, and estimated support price and dollar value. Runner cultivars generally performed better in Georgia than did virginias although some virginia cultivars developed in Georgia were competitive with superior runners. The runner cultivar with the greatest value per hectare in this study was Georgia-12Y; the virginia cultivars were Georgia-08V and Georgia-11J. There was interaction between water regimes and entries for all reported traits except estimated dollar value. For pod yield and 100-seed weight the interaction was solely between water regimes and market types, for TSMK and length of season it was solely between water regimes and entries within market types, and for estimated support price it was both. In general, the effect of irrigation was more substantial on grade of virginia market-types than it was on runners while runners responded more to irrigation for pod yield than did virginias (982 vs. 782 kg ha−1, P<0.0169). Interaction of water regimes with specific entries within market types was in the main a matter of varying degree of effect of irrigation on specific lines but all in the same general direction. The exception was length of season which actually increased under irrigation for the most recent Univ. of Georgia releases, Georgia-10T, Georgia-11J, and Georgia-12Y, while irrigation hastened the maturity of all other lines. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt virus (TSWV), a member of the genus Tospovirus (family Bunyaviridae), is an important plant virus that causes severe damage to peanut (Arachis hypogaea) in the southeastern United States. Disease severity has been extremely variable in individual fields in Georgia, due to several factors including variability in weather patterns. A TSWV risk index has been developed by the University of Georgia to aid peanut growers with the assessment and avoidance of high risk situations. This study was conducted to examine the relationship between weather parameters and spotted wilt severity in peanut, and to develop a predictive model that integrates localized weather information into the risk index. On-farm survey data collected during 1999, 2002, 2004, and 2005 growing seasons, and derived weather variables during the same years were analyzed using nonlinear and multiple regression analyses. Meteorological data were obtained from the Georgia Automated Environmental Monitoring Network. The best model explained 61% of the variation in spotted wilt severity (square root transformed) as a function of the interactions between the TSWV risk index, the average daily temperature in April (TavA), the average daily minimum temperature between March and April (TminMA), the accumulated rainfall in March (RainfallM), the accumulated rainfall in April (RainfallA), the number of rain days in April (RainDayA), evapotranspiration in April (EVTA), and the number of days from 1 January to the planting date (JulianDay). Integrating this weather-based model with the TSWV risk index may help peanut growers more effectively manage tomato spotted wilt disease.