Are nonwoven synthetic pollination bags a better choice for sorghum breeding?

This work investigated the effects of seven pollination bag treatments on three varieties of sorghum for: grain loss to birds; total weight of five panicles (g); total grain weight of five panicles (g); average grain weight per panicle (g); germination per cent; and occurrence of grain mold during 2016. Varieties were: 1167048 hybrid (brown seeded); BR007B (red seeded); and P9401 (white seeded). The bag treatments were: 1. No bagging; 2. Kraft paper; 3. Kraft paper + plastic bag screen; 4 Used duraweb® SG1; 5. Used duraweb® SG2; 6. New duraweb® SG1; 7. New duraweld® SG2. High bird pressure resulted in 100% seed loss on uncovered panicles and 75% under Kraft paper pollination bags. Birds preferred white seeded P9401, which led to no seed recovery under Kraft paper bags. There was virtually no bird damage with all other pollination bags. For panicle and grain yields the varieties performed in the order 1167048>BR007B>P9401. Unprotected panicles and paper bag treatments had the lowest yields. Panicles covered with the new synthetic bags exhibited 195 to 652% higher yields compared to Kraft paper bags. Varieties x bag type interactions were not important as they contributed 4 to 6% to the total sum of squares for yield traits. Germination test under normal and stress conditions showed no significant adverse effect of bag treatments on seed health. Reused bags performed as well as new bags for all of these traits. Varieties differed significantly for the occurrence of five grain mold pathogens, with highest occurrence of Alternaria, up to 40%, on 1167048 hybrid. Of the five pathogens, bag types differed significantly for Phoma with the highest occurrence of 9% on re-used duraweb®SG2 bags. Thus bags require disinfecting and cleaning before re-use. It is concluded that nonwoven synthetic bags are a better choice than the Kraft paper pollination bags for increasing the grain yield and virtually eliminating the bird damage in sorghum

Termite resistance of DMDHEU-treated wood.

Four field trials were conducted with wood modified with dimethyloldihydroxy-ethyleneurea (DMDHEU) in contact with subterranean termites. Trials 1 to 3 were conducted with Coptotermes acinaciformis (Froggatt); 1 and 2 in south-east Queensland, and 3 in northern Queensland, Australia. Trial 4 was conducted in northern Queensland with Mastotermes darwiniensis (Froggatt). Four timber species (Scots pine, beech, Slash pine and Spotted gum) and two levels (1.3 M and 2.3 M) of DMDHEU were used. The tests were validated. DMDHEU successfully prevented damage by C. acinaciformis in south-east Queensland, but not in northern Queensland. It also did not protect the wood against M. darwiniensis. Except for beech in trial 4, DMDHEU led to reduced mass losses caused by termite attack compared to the unmodified feeder stakes. Slash pine (in trials 1 and 3) and Spotted gum (in trial 1) presented low mass losses. Modification of Scots pine was more effective against termite damage than the modification of beech

Inibição do crescimento de raiz pelo alumínio e toxidez por prótons em milho.

Com o objetivo de investigar a tolerancia diferencial de linhagens de milho ao Al e sua interacao com alta atividade de protons, foram conduzidos dois experimentos em solucao nutritiva. No primeiro foram avaliadas seis linhagens de milho e quatro doses de Al (0, 55, 111 e 222 M) e no segundo as mesmas linhagens e quatro valores de pH (3,8, 4,2, 4,6 e 5,0). Verificou-se que a melhor separacao entre os materiais tolerantes e sensiveis ocorreu na dose de 222 M de Al, visto que em doses mais baixas deste elemento houve estimulo do crescimento radicular, sendo este mais acentuado nas linhagens SLP 181 e L 3, tolerantes ao AL. Entretanto o estimulo do crescimento foi temporario e a toxidez se manifestou apos cinco dias de tratamento. Quatro linhagens estudadas foram sensiveis a alta atividade de protons, sendo duas tolerantes ao Al e duas sensiveis. Conclui-se que em milho nao houve correlacao definida entre tolerancia ao Al e tolerancia a alta atividade de protons, em solucao nutritiva

Como utilizar grãos de sorgo no preparo de produtos caseiros.

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