ABSTRACT A field study at three highland sites near Quito, Ecuador, was conducted to determine whether host-diversity effects on potato late blight would be as important as recently found in studies conducted in temperate areas. We compared three potato mixtures and use of mixtures in combination with different planting densities and two fungicide regimes. Treatment comparisons were made by abs...

Tagged Colorado potato beetles (CPB), Leptinotarsa decemlineata (Say), were released on potato plants, Solanum tuberosum L., and tracked using a portable harmonic radar system to determine the impact of host plant spatial distribution on the tendency of the pest to remain on the colonized host plant or patch. Results confirmed the long residency time on the host plant and showed that close conn...

Mesotrione is an effective herbicide for volunteer potato control but is not selective in several crops, including onion and carrot. Studies were conducted in 2006 to evaluate the effectiveness of wiper-applied mesotrione for control of volunteer potato in a potato crop. Surprisingly, nontreated potatoes growing adjacent to mesotrione-treated plants exhibited bleaching symptoms resembling mesot...

Zebra Chip disease is a serious threat to potato production. The pathogen, the phloem-limited bacterium 'Candidatus Liberibacter solanacearum,' is vectored by the potato and tomato psyllid Bactericerca cockerelli to potato and tomato. Patterns of pathogen translocation through phloem in potato and tomato plants were examined to determine whether rate or direction of translocation vary by host s...

A new potato tuber lipoxygenase full-length cDNA sequence (lox1:St:2) has been isolated from potato tubers and used to express in Escherichia coli and characterize a novel recombinant lipoxygenase (potato 13/9-lipoxygenase). Like most plant lipoxygenases it produced carbonyl compounds from linoleate (the preferred substrate) and was purified in the Fe(II) (ferrous) state. Typical of other potat...

The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) is a serious pest of potato and other solanaceous crops. B. cockerelli has been associated with the bacterium "Candidatus Liberibacter solanacearum" (Lso), the causal agent of zebra chip, a new and economically important disease of potato in the United States, Mexico, Central America, and New Zealand. The biology of liberi...

One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related...

Abstract To find out how maize and potato can grow and develop in an intercropping system rather than each grown alone in a sole cropping system the following factorial experiment was performend in the frame-work of a randomized complete block three replications in the experimental farm of the faculty of agriculture, Zanjan University in year 2004. Different potato to maize ratios of (1:0), i...

Two proteinase inhibitors have been isolated from tubers of potato (Solanum tuberosum). Based on N-terminal amino acid sequence homologies, they are members of the Kunitz family of proteinase inhibitors. Potato Kunitz inhibitor-1 (molecular weight 19,500, isoelectric point 6.9) is a potent inhibitor of the animal pancreatic proteinase trypsin, and its amino terminus has significant homology to ...

Potato quality control has improved in the last years thanks to automation techniques like machine vision, mainly making the classification task between different quality degrees faster, safer and less subjective. In our study we are going to design a computer vision algorithm for grading of potatoes according to the greening of the surface colour of potato. The ratio of green pixels to the tot...