After germination, plants enter juvenile vegetative phase and then transition to an adult vegetative phase before producing reproductive structures. The character and timing of the juvenile-to-adult transition vary widely between species. In annual plants, this transition occurs soon after germination and usually involves relatively minor morphological changes, whereas in trees and other perenn...

Twenty-nine herbaceous perennial ornamentals were evaluated for root galling after 2 months in soil infested with Meloidogyne hapla u n d e r greenhouse conditions. Plants such as Asclepias, Epimedium, Liriope, Lithospermura, Myosotis, Penstemon, Sidalecea, and Solidago did not have galls or egg masses present on the root system and were rated as resistant. Astrantia, Boltonia, Centranthus, and...

Within highway rights-of-way, native perennial grasses provide desirable services to support natural and human constructed ecosystems. However, native perennial grass establishment in annual grass dominated roadsides of semiarid and Mediterranean climates of the western United States requires specific cultural and chemical management treatments to control weeds. In 2004, field studies were cond...

Populations of the rare annual forb Amsinckia grandiflora may be declining because of competitive suppression by exotic annual grasses, and may perform better in a matrix of native perennial bunchgrasses. We conducted a field competition experiment in which Amsinckia seedlings were transplanted into forty 0.64-m 2 experimental plots of exotic annual grassland or restored perennial grassland. Th...

Roots of perennial plants have both persistent portion and fast-cycling units represented by different levels of branching. In woody species, the distal nonwoody branch orders as a unit are born and die together relatively rapidly (within 1-2 years). However, whether the fast-cycling units also exist in perennial herbs is unknown. We monitored root demography of seven perennial herbs over two y...

Plant strategy and life-history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life-history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition...

Hybrids between maize (Zea mays L.) and perennial teosinte (EuMaena perennis Hitchc.) offer a favorable opportunity to follow the behavior of triplicate sets of chromosomes in a triploid hybrid. Maize, the diploid parent, has been carefully analyzed both genetically and cytologically. Perennial teosinte seems to be unquestionably a true tetraploid. Its tetraploid character is evident from (1) t...

Following the flurry of plant exploration in the 1950's, most activity with the plants collected apparently centred on expanding the area of adaptation of perennial grass and annual legume. Many of the subsequently released grass cultivars have been agronomically successful but have not been adopted. Haifa white clover, released by the New South Wales Department of Agriculture 25 years after co...

Cell culture and genetic engineering techmques can be used to develop improved pasture plants. To utltise these methods we have developed procedures for regenerating plants from tissue cultures of perennial ryegrass and white clover. In both, the plant genotype influences regeneration capacity. There was significant genetic variation among regenerated perennial ryegrass plants in a wde range of...

Endophytic fungi live their whole life within host tissues usually without any visible symptoms. Their vertical transmission (seed-plant-seed) has been well described and documented. However, horizontal transmission (plant-plant) needs more clarification. The aim of this study was to assess the extent to which endophytes move vertically in ecotypes of perennial ryegrass and whether there is evi...