There are by now several attempts to make the theory of the field of one element F1 rigorous. In [10] the authors formalize the transition from rings to schemes on a categorial level and apply this machinery to the category of sets to obtain the category of F1-schemes as in [1]. In [3] and [5] the authors extend the definition of rings in order to capture a structure that deserves to be called ...

In an earlier work, we showed that if the Hodge conjecture holds for all complex abelian varieties of CM-type, then the Tate conjecture holds for all abelian varieties over finite fields (Milne 1999b). In this article, we extract from the proof a statement (Theorem 1.1) that sometimes allows one to deduce the Tate conjecture for the powers of a single abelian variety A over a finite field from ...

As a major cereal crop, rice (Oryza sativa L.) is crucial to food security for at least half the world population. New varieties with high yield potential, good quality and high resistance to biotic and abiotic stresses are needed in order to meet the demand for more food arising from the rapid human population growth and concurrent decrease in arable land. Improvement of rice quality has now b...

Land transfers play a vital role in determining the level of farm machinery service and variety selection by scattered land reduction contiguous enhancement, which are also conducive to poverty alleviation welfare utilization. Based on micro-survey data 898 kiwifruit growers Shaanxi Province, this paper analyzed effect adoption new varieties propensity score matching (PSM) technology. A stepwis...

Salinity stress is a major abiotic factor that affects crop output, and as a pioneer crop in saline and alkaline land, salt tolerance study of cotton is particularly important. In our experiment, four salt-tolerance varieties with different salt tolerance indexes including CRI35 (65.04%), Kanghuanwei164 (56.19%), Zhong9807 (55.20%) and CRI44 (50.50%), as well as four salt-sensitive cotton varie...

Many centers of crop domestication and diversity are experiencing rapid changes in agriculture practices resulting in the loss of crop varieties and the knowledge and customs that have sustained them (Brush 2004; Harlan 1975). Germplasm diversity is threatened by several factors including: replacement by high-yielding varieties, a shift to cash crop cultivation, change in land use, economic inc...

Drought stress caused by unpredictable precipitation poses a major threat to food production worldwide, and its impact is only expected to increase with the further onset of climate change. Understanding the effect of drought stress on crops and plants' response is critical for developing improved varieties with stable high yield to fill a growing food gap from an increasing population dependin...

monogerm and multigerm seed varieties are used in sugar beet cultivation. singling is inevitable and mechanization almost impossible when multigerm seed varieties are used. for this and for some other reasons, economically sound and fully mechanized cultivation of sugar beet calls for the use of monogerm seed varieties. throughout europe, only monogerm varieties are used in sugar beet productio...

In a marketing environment, the demand conditions, the costs of shipping and storing grain varieties, the interest rate on farm loans, and the distribution of cropland in the area are important determinants of growers’ planting decisions. In this article, I focus on a market for two quality-differentiated agricultural commodities: one produced with the use of biotechnology and the other, withou...