Red clover (Trifolium pratense L.) is one of the most important legume forage species in temperate livestock agriculture. Tetraploid red clover cultivars are generally producing less seed than diploid cultivars. Improving the seed setting potential of tetraploid cultivars is necessary to utilize the high forage quality and environmentally sustainable nitrogen fixation ability of red clover. In ...

Interspecific hybrids were obtained in an otherwise incompatible cross Brassica juncea x Brassica tournefortii through in vitro culture of hybrid embryos. The best response was observed from culture of embryos excised 20 days after pollination on MS medium supplemented with kinetin, alpha-naphthylacetic acid, gibberellic acid, glutamine and casein hydrolysate. One hybrid plant had many distinct...

Single radial immunodiffusion was used to study the self-incompatibility (S) proteins present in stigmas of two inbred lines of Brassica oleracea: a self-incompatible line and a self-compatible mutant derived from it. The genetic basis of observed quantitative differences in S proteins between the two inbreds was shown to be determined by a single gene with dosage effects. Self-pollination of i...

The reproductive assurance hypothesis states that self-incompatible female plants must produce twice the number of seeds relative to their self-compatible hermaphroditic counterparts to persist in gynodioecious populations. This is a viable life-history strategy, provided that pollination rates are sufficiently high. However, reduced pollination rates in alpine plants are likely due to climate ...

in fruit trees damage of frost and freezing is depended to time of chillhng and tree phonological stage. almond (prunus amygdalus b. (and apricot (p. armeniaca l.) cultivars are usually the first fruit trees to bloom and susceptible to damaging frosts in the early spring. a study was conducted on different types of almond and apricot cultivars in order to investigation the main factors related ...

PREMISE OF THE STUDY Self incompatibility (SI) in rare plants presents a unique challenge-SI protects plants from inbreeding depression, but requires a sufficient number of mates and xenogamous pollination. Does SI persist in an endangered polyploid? Is pollinator visitation sufficient to ensure reproductive success? Is there evidence of inbreeding/outbreeding depression? We characterized the m...

In ‘McIntosh’ apples (Malus domestica Borkh.), the number of well-formed seeds and the number of fertilized ovules (well-formed plus aborted seeds) were correlated to yield an index of asymmetry for individual fruit. In spite of different flowering and pollination conditions in 1990 and 1991, the index of asymmetry decreased curvilinearly with increases in the number of well-formed seeds and of...

Functional diversity has been postulated to be critical for the maintenance of ecosystem functioning, but the way it can be disrupted by human-related disturbances remains poorly investigated. Here we test the hypothesis that habitat fragmentation changes the relative contribution of tree species within categories of reproductive traits (frequency of traits) and reduces the functional diversity...