a long-term rotation experiment was established in 2001 to compare conservation or reduced tillage systems (shallow rototiller and chisel tillage) with conventional tillage system using mouldboard plough in a semi-arid region with mediterranean climate. field experiments were conducted to determine weed density and profitability of cropping systems in a crop rotation of winter wheat (triticum a...

Biomass crops are being promoted as environmentally favorable alternatives to fossil fuels or ethanol production from maize (Zea mays L.), particularly across the Corn Belt of the United States. However, there are few if any empirical studies on inorganic N leaching losses from perennial grasses that are harvested on an annual basis, nor has there been empirical evaluation of the hydrologic con...

To determine the most economical and efficient means to maintain cultures of Maize chlorotic dwarf virus (MCDV) and to screen for host plant resistance to MCDV, we evaluated the effects of temperature, light intensity, daylength, atmospheric pressure, and leafhopper gender on the frequency of transmission of MCDV by Grarminella nigrifrons Forbes (Homoptera: Cicadellidae). Female leafhoppers tra...

The worldwide production of maize (Zea mays L.) is frequently impacted by water scarcity and as a result, increased drought tolerance is a priority target in maize breeding programs. While DREB transcription factors have been demonstrated to play a central role in desiccation tolerance, whether or not natural sequence variations in these genes are associated with the phenotypic variability of t...

Activity of the enzyme ADPglucose pyrophosphorylase is known to be reduced in maize (Zea mays L.) endosperm mutants at two independent loci, Shrunken-2 (Sh(2)) and Brittle-2 (Bt(2)). Spinach leaf ADPglucose pyrophosphorylase has previously been shown to comprise two subunits of 51 and 54 kilodaltons. Anti-bodies raised to each of the two subunits of spinach leaf ADPglucose pyrophosphorylase wer...

Maize (Zea mays L.) is truly a remarkable crop species, having been adapted from its tropical origins to a wide diversity of environments and end uses. According to the Food and Agriculture Organization of the United Nations FAOSTAT webpage, 792 million metric tons of maize were produced worldwide in 2007, making it the world’s highest yielding grain crop (http://faostat.fao.org/site/339/defaul...

The GST (EC 2.5.1.18) family of enzymes are well known for their role in the detoxification of various xenobiotic compounds in both plant and animal systems. These enzymes facilitate the addition of GSH, y-glutamylcysteinylglycine, to an electrophilic site of a suitable substrate, yielding a GSH conjugate. In maize (Zea mays), the GSH-conjugation reaction is responsible for the metabolism of se...

Nitrogen is considered the most limiting nutrient for maize (Zea mays L.), but there is limited understanding of the regulation of nitrogen-related genes during maize development. An Affymetrix 82K maize array was used to analyze the expression of ≤ 46 unique nitrogen uptake and assimilation probes in 50 maize tissues from seedling emergence to 31 d after pollination. Four nitrogen-related expr...

Intercropping, which grows at least two crop species on the same pieces of land at the same time, can increase grain yields greatly. Legume-grass intercrops are known to overyield because of legume nitrogen fixation. However, many agricultural soils are deficient in phosphorus. Here we show that a new mechanism of overyielding, in which phosphorus mobilized by one crop species increases the gro...

Endophytes are microorganisms that inhabit plant tissues without causing disease. Some endophytes help their hosts to combat pathogens. Here we explored the hypothesis that the plant-derived foods consumed by humans and other animals host endophytes that also antagonize foodborne pathogens or food-rotting agents. Our laboratory previously cultured a library of bacterial endophytes from differen...