—Many desert perennials are long-lived, but there are few data on ages or population structures of desert plants. We used 2 methods to estimate ages of a population of Yucca brevifolia (Joshua tree) in southwestern Utah from a 14-year census of plant sizes. Plant height at the 1st census ranged from 0.08 m to 6.0 m, and trees grew in height at a mean rate of 3.75 cm ⋅ yr–1. Plants also increase...

During maize development and reproduction, shading stress is an important abiotic factor influencing grain yield. To elucidate the genetic basis of shading stress in maize, an F(2:3) population derived from two inbred lines, Zhong72 and 502, was used to evaluate the performance of six traits under shading treatment and full-light treatment at two locations. The results showed that shading treat...

in order to determine the best form factor formula for loblolly pine (pinus taeda l.) plantations in talesh (western guilan province-iran), a number of 110 trees were selected based on their distribution in diameter classes, from 12 to 34 cm (in a two- cm diameter interval). first, several quantitative factors including diameter at breast height, diameter at 0.65 m of height, and diameter at st...

In the floriculture industry, the need for heat tolerant bedding plant cultivars is increasing because of the rising temperature around the world. A pot experiment was carried out to examine the impacts of four heat stress durations (0, 7, 14 and 21 days) on growth and ornamental traits to determine the relative heat tolerance of four cultivars of calendula (Calendula officinalis). Growth and d...

a pot experiment was carried out to determine the effect of foliage spraying of silicon (si) on growth and ornamental characteristics of calendula grown under salt stress and greenhouse conditions. a factorial experiment based on completely randomized design was conducted with 3 levels of si (0, 50 and 100 mg/l) and 3 levels of nacl (0, 100 and 200 mm) with 4 replications. at flowering stage, s...

the effects of sodium chloride (nacl) salinity (control; canal water with 0.4 ds m-1), 2.5 dsm-1, 5.0 ds m-1, 7.5 ds m-1 and 10.0 ds m-1, respectively) developed after 6 weeks of pruning (beginning of study) on plant growth, flowering and quality of three cut rose (rosa hybrida l.) cultivars viz. ‘kardinal’, ‘angelique’ and ‘gold medal’ were studied to achieve better management, quality product...

milkthistle (silybum marianum l.) is a rangeland medicinal plant growing wild in different locations in iran. in the present research work, the effect of n, p and k in their different proportions of n0p0k0, n100p100k50, n150p150k100 and n200p200k150 kgha-1 as compared with control (no fertilizer application) on the plant's growth was put to test. suc variables as plant height, no. of capit...