Field experiments were conducted under rain-fed conditions to study the growth and photosynthetic efficiency of transgenic Bt cotton hybrids during 2002-03 and 2003-04 seasons. Three Bt cotton hybrids (Bollgard 1) and their nonBt (NBt) counterparts viz. MECH 12, MECH 162, and MECH 184 were grown along with a local hybrid NHH44. Growth parameters such as plant height, main-stem nodes, biomass accumulation, and physiological processes like stomatal conductance (g s ), and rates of transpiration (E) and photosynthesis (P N ) did not differ significantly between Bt and NBt hybrids up to 80 DAS (d after sowing). Squaring commenced at 50 DAS both in Bt and NBt. The loss of young fruiting forms by the entomological factors was three times less in Bt than NBt. As a consequence, Bt had more early formed bolls on the lower canopy which contributed to higher biomass and seed cotton yield. On the other hand, bolls distributed intermittently in NBt. Heavy boll load altered the growth and physiological processes, and as a result Bt had higher g s , E, and P N than NBt. Since developing bolls (sink) divert the saccharides and nutrients from other organs, Bt plants with heavy boll load senesced early and stopped the production of new squares and bolls. Thus, the boll load influenced the change in growth and physiological processes of Bt from NBt.

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Corn is a vital food source for human consumption, animal feed as well as industrial processing. However, corn faces repeated spoilage and contamination by a huge range of fungi especially by Fusarium and Aspergillus species. These fungi are known of producing mycotoxins such as fumonisins (FBs), moniliformin (MON), zearalenone (ZEA), beauvericin (BEA) and aflatoxins (AFs). The main objective of this study was to quantify the mycotoxins produced by both fungi associated with cornmeal in Malaysia. The extracted mycotoxins were qualitatively analyzed using A. salina bioassay, and quantitatively using Ultra-fast Performance Liquid Chromatography (UFLC). Three hundred and fourteen isolates of microfungi were obtained, 90.5% isolates belonged to Aspergillus species, namely A. flavus (76.8%), A. niger (7.6%), A. nidulans (4.5%) and A. fumigatus (1.6%). Another 9.6% isolates were Fusarium species, identified as F. verticillioides (4.5%), F. semitectum (3.2%) and F. proliferatum (1.9%). As for the mycotoxin analysis, out of 40 isolates of Aspergillus, 29 isolates produced AFB 1 and only two isolates produced AFB 2 . Fifteen out of 16 Fusarium isolates produced MON, 12 isolates produced BEA and all isolates produced FB 1 , but none of them produced ZEA. The analysis of A. salina revealed that all the five mycotoxins extracts were toxic to the brine shrimp despite the concentration of the mycotoxins.