A gas chromatographic technique is described for determination of beta-methallyl chloride applied to small samples of wheat. Sorption after 24 hr exposure was high, varying from 63.7 to 70.2% of the initial dosage, but was significantly reduced by lower wheat moisture content. Methallyl chloride has potential as an alternative fumigant for disinfesting small grain sacks and seed stocks for livestock.

The application of different combinations of mineral fertilizers had no significant influence on wheat entomofauna. The insect species in the trial plot detected were uniformly represented except for grain aphids whose number varied significantly. Numerous colonies of Sitobion avenae and Metopolophium dirhodum were estimated following the spring treatment employing highest nitrogen application amount (285 kg/h KAN). Greatest leaf damage caused by cereal leaf beetle (Lema melanogaster L.) larvae amounted to 21.7 and has been recorded following the use of an optimal NPK application rate, whereby the nitrogen-containing fertilizer had been employed in spring treatment.

In 1987-88 and 1988-89, field plot experiments were undertaken to assess the effects of wheat spindle streak mosaic virus (WSSMV), a soilborne virus transmitted by Polymyxa graminis, on winter wheat yields in New York. Two experimental approaches, reinfestation of fumigated plots with nonfumigated soil and a natural gradient of disease incidence, were used to produce different levels of disease. To minimize problems of covarying soil factors, yields of susceptible cultivars were compared with resistant cultivars in each experiment. The most reliable estimates of WSSMV effect were obtained with the disease gradient method when average disease incidence varied greatly between blocks and replication was high (12 blocks). Based on this approach, the grain yield of the susceptible cultivar Frankenmuth was reduced by an average of 14 kg/ha for every 1 percent increase in plants infected by WSSMV, a 1.4-t/ha (32%) reduction when all plants were infected. Yields of the breeding line NY6432-10 did not decline, despite a high incidence of plants infected with the virus in both years. When data from 1980-1989 regional yield trials were compared with temperature data, significant correlations were detected between long spring periods of temperatures conducive to WSSMV and lower yields of the susceptible cultivars Frankenmuth and Augusta relative to the yield of the highly resistant cultivar Geneva. Relative yield of Frankenmuth decreased by an average of 0.45% per day as net days in the optimal temperature range (2-11 C) increased from 20 to 45. Yield reductions for other cultivars screened over the past decade closely paralleled their relative resistance to, or tolerance of, WSSMV as demonstrated in field plot experiments. These results indicate that WSSMV has significantly reduced the yield of susceptible cultivars in New York over the past decade and that yield reduction is related to the percentage of plants infected with the virus and the duration of spring temperatures conducive to disease development.

Der Einfluss der thermisch-mechanischen Behandlungsverfahren Extrusion und Flockierung von Weizen auf das Stoffsystem wird eroertert. In einem Versuchsansatz wurde der Frage nachgegangen, inwieweit der haeufig als In-vitro-Test eingesetzte Amyloglucosidase-Test ausreichend stoffliche Veraenderungen im relativen Vergleich bei veraenderten Prozessparametern charakterisiert und inwieweit diese Werte auch bei der Tierfuetterung relevant sind. Es zeigte sich, dass der Grad des Staerkeaufschlusses, ermittelt nach der Amyloglucosidasemethode, nicht zur Charakterisierung und Bewertung bei der Verfuetterung ausreicht. Weitere Untersuchungen werden als notwendig erachtet. [S-93-00409]

A field experiment was conducted during 1978-81 to study the effects of green manure (Sesbania aculeata) incorporation in wetland rice and maize on soil physical properties, and root growth and yield of following wheat on a loamy sand soil under sub-tropical climate of northern India. Application of green manure to wetland rice increased the water stable aggregates, reduced the soil bulk density and increased infiltration rate. The effects of green manure in maize were relatively small.

The mineral composition of winter wheat, var. Astral, growing in twelve field experimental plots was determined at the tillering, anthesis and harvest stages respectively. Leaf nitrogen at the anthesis stage was the parameter affected at a greater extent by addition of nutrients. Aerial part weight was also affected though to a lesser extent. No significant differences for potassium and magnesium contents at the tillering and anthesis stages, respectively, were found. Rainfall introduced variability in the results. Nitrogen addition showed the greatest effect on yield increase and on the mineral composition of the plant. The anthesis was shown to be the most important stage in plant nutrition. A discussion on how to achieve optimal nutrition values is made | [La composizione minerale del grano var. Astral, cresciuto in dodici campi sperimentali, e' stata determinata rispettivamente alla levata, alla fioritura e alla raccolta. L'azoto delle foglie allo stadio di levata era il parametro in piu' larga misura influenzato dall'aggiunta di nutrienti. Anche il peso della parte aerea era influenzato, sebbene in minor misura. Non si sono riscontrate differenze significative per i contenuti di potassio e magnesio rispettivamente agli stadi di levata e fioritura. La caduta di pioggia ha implicato una variabilita' dei risultati. L'aggiunta di azoto ha mostrato l'effetto maggiore sull'aumento di resa e sulla composizione minerale della pianta. La fioritura si e' rivelata lo stadio piu' importante nella nutrizione della pianta. Viene discusso su come raggiungere valori nutritivi ottimali]

This study clearly shows that development of wheat anthers and pollen is affected by B deficiency. It also shows a good correlation between anther length and pollen development. In B-deficient wheat, the pollen does not accumulate starch and the nuclei when present are abnormal. It has been suggested that B-deficiency affects pollen development during the pollen mother cell stage. The results show that B is essential for wheat pollen germination and pollen tube growth. B may play a role in the control of protein secretory activity in pollen tubes through the redistribution and capture of materials including (and especially) protein from membrane fusion events involving vesicles, which lead to pollen tube extension