Research Professor, Systems Ecology Research Group, San Diego State University, San Diego, Calif., 92182. Abstract: Photosynthesis and respiration rates were determined for chaparral shrubs as a function of temperature and/or light intensity. In mature stands at Echo Valley, Calif., net seasonal carbon assimilation by leaves ranges -2 from a dry weight equivalent of 673 g m -1 in -2 pure stands...

A mathematical model is developed for converting between the two measurement bases commonly used in the construction of growth profiles in solid-state fermentation, namely absolute mass ratio m(dry biomass)/m(initial dry matter) and relative mass ratio m(dry biomass)/m(dry matter). These are not equivalent, due to the loss of dry matter as CO2 during the fermentation. The model is equally appli...

1. We had two objectives: (i) to determine the generality of, and extend the applicability of, a previously reported empirical relationship between leaf-level net photosynthetic rate ( A M , nmol g − 1 s − 1 ), specific leaf area (SLA, m 2 kg − 1 ) and leaf nitrogen mass fraction ( N M , mmol g − 1 ); and (ii) to compare these empirical results with a mechanistic model of photosynthesis in orde...

to study the effects of plant density and nitrogen rates on the ability of canola (regent  cobra; an inbred variety) to compete with weeds, an experiment was conducted as a factorial complete block design with four replications. the treatments included four levels of plant density at 150, 190, 230, and 270 plants m-2, and four levels of nitrogen (n) fertil-izer at 0, 46, 92, and 138 kg ha–1. r...

The aim of this study was to determine the effects of a bacterial inoculant and chemical additives on nutrient composition, in vitro degradation, total loss, aerobic stability, microbiological quality, and fermentative profile of sugarcane silage. Treatments were distributed to forty-eight mini-silos in a 2 × 4 factorial arrangement: two levels of microbial inoculant (INO, 0 or 4 g/t of fresh s...

Ten male Merghoz goats with initial live weights of 29.2 ± 1.2 kg (Mean±SE) were used to investigate the effect of natural changes in photoperiod on dry matter intake (DMI) and reproductive activity during a 365 day study. The bucks were housed in individual pens, under natural daylength condition at west of Iran, Kermanshah (34˚ 18¢N and 47˚ 3¢E and 1420 m above sea level). A diet was offered ...

ten male merghoz goats with initial live weights of 29.2 ± 1.2 kg (mean±se) were used to investigate the effect of natural changes in photoperiod on dry matter intake (dmi) and reproductive activity during a 365 day study. the bucks were housed in individual pens, under natural daylength condition at west of iran, kermanshah (34˚ 18¢n and 47˚ 3¢e and 1420 m above sea level). a diet was offered ...

The objective the present study was to determine the influence of a supplemental methionine analogue, the isopropyl ester of 2-hydroxy-4-(methylthio)-butanoic acid, commercially available as MetaSmartTM, on lactation performance, particularly milk protein production. The effects of this preparation were compared with those of a rumen-protected form of methionine, marketed as SmartamineTM M. Exp...