You are looking at 1 - 5 of 5 items for
- Author or Editor: A. Ahmedullah x
Clusters of four varieties of table grapes were packed in TKV lugs and fumigated with 4, 6, or 8 Deccodione Smoke Tables (DST) for a period of 30 minutes in a fumigation chamber. After fumigation, inoculum of Botrytis cineraria was placed among the berries in the clusters in predetermined locations. Fruit was stored at 0C and high relative humidity for up to 16 weeks. Fruit was examined at 4, 8, 12, and 16 weeks of storage. Decay control index, freshness of stems, and bleaching of pigments around the capstem was recorded at each evaluation time. Size of aerosol particles was determined. Satisfactory control of decay was obtained with 8 DSTs. Lower doses failed to give satisfactory decay control. Bleaching of capstems typically seen with sulfur dioxide fumigation was not noticed with DST fumigation.
Field-grown grapes (Vitis labruscana Bailey cv. Concord) were fertilized preplant with four levels of N and S, two levels of P and B, and three levels of K and Zn. Vine growth and yield responded to N up to 180 kg·ha−1. Increasing N to 270 kg·ha−1 increased vine growth at the expense of yield. There was no growth or yield response to P, K, and S, either alone or synergistically with N. Yield was significantly correlated with cluster number and cluster weight. Fertilizer treatments had no significant effect on quality. Nitrate-N, P, and K in the leaf petioles increased with increasing fertilizer levels of these elements and decreased as the season advanced.
Table grapes cvs. Flame Seedless, Black Monukka and Canadice were fumigated with 2 levels of Deccodione smoke tablets for 30 minutes. Grapes were packed in TKV lugs with Botrytis inoculum planted among the clusters and stored at 0° C for up to 9 weeks. Size of smoke particles was determined. Fruit was evaluated at weekly intervals for decay and quality parameters. Deccodione residues on fruit were determined and found to be within acceptable limits set for this chemical. It was possible to store the grapes for up to 4 weeks at 0° C in good condition. Beyond this period effect of fumigation was lost. There was no bleaching of pigments around the capstem as is seen with sulfur dioxide fumigation. Storage for prolonged periods will necessitate increasing the dose of Deccodione tables and/or repeating the fumigation.
Ring-labeled [14C] 2,4-D was applied to mature leaves of pot-grown ‘Concord’ grape plants at concentrations of 500 and 1000 ppm. The absorption, translocation and metabolism of 2,4-D was determined 1, 2, and 3 weeks after application. No further absorption occurred 1 week after application. Translocation was mostly acropetal and appears to have taken place in the first week. 2,4-D is metabolized extensively by ‘Concord’ to nonpolar and polar metabolites and insoluble residue. The ethyl acetate, water soluble and ethanol insoluble fractions were 47%, 9%, and 31%, respectively, of total 14C extracted from the treated leaf. Chemical name used: (2,4-dichlorophenoxy)acetic acid (2,4-D).
Paclobutrazol, trunk-applied at 3 stages of vine growth, reduced the shoot length of Vitis labruscana Bailey ‘Concord’ vines. Budbreak was delayed by 3-5 days in treated vines compared to controls. There was no effect of treatments on pruning weight, fruit quality, and midwinter cold hardiness of buds. Chemical names used: β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).