Cordell soybean is a newly released cultivar resistant to Heterodera glycines (SCN) races 3 and 5. The hectarage infested with these races and with other races that can parasitize Cordell in Tennessee is not known. A survey of races in Tennessee soybean fields with sampling weighted by soybean hectarage on a county basis was conducted in 1988. The SCN race plus female development on Bedford and...

Soybean inoculation with effective rhizobial strains makes unnecessary the use of N-fertilizers in the tropics. A frequently reported problem is the failure of the inoculant strains to overcome the competition imposed by indigenous rhizobial populations. The screening of indigenous rhizobia, already adapted to local conditions, searching for highly effective strains for use as inoculants repres...

The objective of this study was to determine the appropriate growth stage of inflorescence (spathe) explants among different cultivars of the date palm (Phoenix dactylifera L.) and to define the optimum period of incubation on high-auxin medium. Inflorescence explants were excised from seven Pakistani cvs. at different growth stages and cultured on a basal MS medium containing 100 mg l 2,4-D fo...

The relative susceptibility of 44 genotypes of wild Fragaria L. and commercial cultivars of strawberry Fragaria ×ananassa Duch. to Meloidogyne hapla Chitwood and Pratylenchus penetrans (Cobb) Filipjev & Shuurmans Stekhoven was evaluated in the greenhouse. Eleven genotypes were highly resistant to populations of M. hapla from Washington State and Oregon, with Rf values (initial nematode density/...

This study tests the effect of glyphosate application on disease severity in glyphosate-resistant sugar beet, and examines whether the increase in disease is fungal or plant mediated. In greenhouse studies of glyphosate-resistant sugar beet, increased disease severity was observed following glyphosate application and inoculation with certain isolates of Rhizoctonia solani Kuhn and Fusarium oxys...

Sensitivity to ozone of pollen germinating in vitro is closely correlated with ozone sensitivity of the pollen parent. Ozone-sensitive and tolerant pollen populations have been identified in tobacco, petunia, and tomato cultivars. The rate of tube elongation can be reversibly slowed or stopped by exposure to low concentrations of ozone. Tube growth rates in the presence of a range of ozone dosa...

The tomato leafminer Tuta absoluta Meyrick is a key insect pest of tomato in Tunisia and in many other countries around the world. The present study was carried out to attempt to acquire better knowledge of the biology of this insect and to implement suitable prophylactic control tools for T. absoluta in Northeastern Tunisia. Under greenhouse conditions, T. absoluta females exhibited a stronger...

Measurement of fresh tomato fruit overall quality, and particularly lycopene content, is challenging in the context of high-volume production. An experiment was conducted to simultaneously measure various quality parameters of tomato in a nondestructive manner using vis-NIR reflectance spectroscopy and chemometrics. The sampling set included different cultivars that are obtainable from both ret...