A simple, fast, repeatable and less laborious sample preparation protocol was developed and applied for the analysis of biocontrol fungus Trichoderma harzianum strain FA1132 by using gas chromatography-mass spectrometry. The match factors for sample spectra with respect to the mass spectra library of fungal volatile compounds were determined and used to study the complex hydrocarbons and other volatile compounds, which were separated by using different capillary columns with nonpolar, medium polar and high polar stationary phases. To date, more than 278 volatile compounds (with spectral match factor at least 90%) such as normal saturated hydrocarbons (C7-C30), cyclohexane, cyclopentane, fatty acids, alcohols, esters, sulfur-containing compounds, simple pyrane and benzene derivatives have been identified. Most of these compounds have not previously been reported. The method described in this paper is a more convenient research tool for the detection of volatile compounds from the cultures of T. harzianum.

Eight sunflower inbred lines were crossed in 8×8 diallel fashion (without reciprocal) and 28 F 1 were developed at Oilseed Research Centre (ORC), Bangladesh Agricultural Research Institute (BARI), Gazipur in Rabi season, 2018. All F 1 and their parents were planted in Rabi season 2019 to estimate general combining ability (GCA) and specific combining ability (SCA) effects for yield and yield attributes. The highly significant mean squares for genotypes for all the studied characters indicating wide variability in the parental materials. The highly significant GCA effects for stem diameter, days to maturity, number of seeds/head, 1000-seed weight and SCA effects for days to 50 flowering, days to maturity, head diameter, number of seeds/head, 1000-seed weight and seed yield were observed. The greater ratio of GCA/SCA implies the predominance of additive gene effect for all the studied characters. The parents, P1, P2, P3, P6 and P8 were found as good general combining parents for short duration, early maturity, lodging resistant, and 1000 seed weight. Crosses with the best SCA effects for some characters were found from the interaction of low × low, high × low, low × high or high × average combining parents. Further investigation on superiority and stability of good combining parents and hybrids over different years and locations is needed.