Biomedical subjects

Lizhen Zhang

Publications and source records attributed to Lizhen Zhang.

3 recordsLinked to original sources

PubMed2005

[A physiological development time-based simulation model for cotton development stages and square- and boll formation].

In this study, three cotton varieties (CRI 36, CRI 35 and CRI 41) were planted in Nanjing, Anyang, Baoding and Shihezi, respectively, in 2002, and the dynamic relationships between their development and environmental factors were analyzed. Based on this, a simulation model for cotton development stages and square-and boll development was built in terms of physiological development time (PDT). In calculating relative thermal effectiveness, the effect of diurnal temperature differences in different regions on cotton development was incorporated, and the enhancement of plastic mulching on air temperature was quantified. To simulate development stages, the initial fruiting node index (IFIN), sunlight duration factor (FSH), and solar radiation index on fruiting branch (IFBR) were introduced, besides earliness factor of a given genotype. The validation of the model with the data obtained from different years, ecological zones, genotypes, and cultivation practices indicated a high goodness of fitness between the simulated results and observed values. The root mean square error (RMSE) between simulated and observed days from sowing to emergence, emergence to squaring, anthesis to boll opening, and sowing to boll opening was 0.9, 2.2, 1.7, and 2.1 d, respectively, with a mean of 2.1 d, and in all plant sites, the RMSE between simulated and observed days from squaring to boll opening was 1.8-3.7 d, and that from squaring to opening was 4.6-5.8 d.

Gossypium↗

PubMed2005

[Dynamics of soil enzyme activity and nutrient content in intercropped cotton rhizosphere and non-rhizosphere].

The study with high yield cotton-wheat double cropping system showed that soil urease, invertase, protease and catalase activities in intercropped cotton field had the same changing trends with those in mono-cultured cotton field, but were significantly higher in intercropped than in mono-cultured cotton rhizosphere and non-rhizosphere at all development stages of cotton. During the intergrowth period of wheat and cotton, soil nutrient contents in intercropped cotton rhizosphere and non-rhizosphere were lower than or had little difference with those in mono-cultured cotton rhizosphere and non-rhizosphere, but became significantly higher after wheat harvested. The changing trends of soil nutrient contents in intercropped cotton field had little difference from those in mono-cultured cotton field, but the nutrient absorption peak appeared late. The soil enzyme activities and nutrient contents were generally higher in rhizosphere than in non-rhizosphere of both intercropped and mono-cultured cotton. Soil nutrient contents had significant (P < 0.05, n = 32) or very significant (P < 0.01, n = 32) correlation with the activities of soil urease, invertase and protease, but had little correlation with soil catalase activity.

Agriculture↗

PubMed2004

[A dynamic knowledge model for nitrogen and water management of cotton].

Through analyzing and extracting the newest research results on nitrogen and water management of cotton, a dynamic knowledge model for decision-making on total nitrogen and water supply levels and their distribution among main growth stages of cotton under different environments and yield targets was developed, with the principles of nitrogen balance and water demand and by integrating the factors of climate, soil, yield and variety. Case studies on the knowledge model with the experiment data sets of different eco-sites, varieties and soil characters indicated a good model performance in decision-making and applicability.

Fertilizers↗