[Isolation and Identification of Bacteria and Mycete from Preservation of Morinda officinalis].

Objective: In order to select antistaling agent which had obvious antibacterial effect on Morinda officinalis, the colony counts of microorganism from the surface of Morinda officinalis and the species of bacteria and mycete were analyzed.

Methods: Bacteria and moulds classification identification method were carried out.

Results: After using 10 g burdock oligosaccharide, 20 g chitosan and 0.

[Leaf redundancy of high-yielding maize (Zea may L.) and its effects on maize yield and photosynthesis].

According to the maize yield at plant density of 15000 ind x hm(-2) in 2007, the leaf-redundant type (cultivar Chaoshi 1) and non-redundant type (cultivar Chaoshi 3) at low plant density were selected, and the changes of their above-ground dry matter accumulation and grain yield after cutting all leaves to 1/2 (T1) and 1/4 (T2) at anthesis at the optimal density and under high-yielding condition were analyzed in 2008, aimed to approach whether the leaf redundancy exists in high-yielding maize colonies. The characters of grain-filling were simulated by Richards' model, and the photosynthetic characteristics and chlorophyll fluorescence of the leaves on ear position were determined to reveal the activities of photosynthesis after the removal of redundancy. The results showed that at optimal plant density and under high-yielding condition, both the redundant and non-redundant types had leaf redundancy.

[Effects of drought stress on the grain yield and root physiological traits of maize varieties with different drought tolerance].

A pot experiment was conducted to study the effects of simulated moderate drought in whole growth period on the grain yield and root physiological traits of drought-tolerant maize variety JK-628 and drought-sensitive maize variety ND-95. Compared with the control, the grain yield of JK-628 and ND-95 under the stress of moderate drought was decreased by 33.7% and 62.

[Effects of controlled-release fertilizers on summer maize grain yield, field ammonia volatilization, and fertilizer nitrogen use efficiency].

A field experiment with colophony-coated fertilizer (CRF) and sulfur-coated fertilizer (SCF) showed that under the same application rates of N, P and K, applying CRF and SCF increased the summer maize grain yield by 13.15% and 14.15%, respectively, compared to the application of common compound fertilizer CCF.

[Spatiotemporal variation of root systems of cytoplasmic male sterile maize (Zea may L.) and its homotype fertile lines].

Maize cytoplasmic male sterile (CMS) lines and their homotype fertile lines were cultivated on soil column to study the differences of their root traits at different growth stages after anthesis. The results indicated that CMS lines had stronger ability of dry matter accumulation in their aboveground part, their grain yield was significantly higher than that of homotype fertile lines (P < 0.05), and their root dry mass was higher.

[Dynamic changes of soil microbial populations and enzyme activities in super-high yielding summer maize farmland soil].

To reveal the characteristics of the dynamic changes of soil microbial populations and enzyme activities in super-high yielding ( > 15,000 kg x hm(-2)) summer maize farmland soil, a comparative study was conducted in the experimental fields in National Maize Engineering Research Center (Shandong). On the fields with an annual yield of >15,000 kg x hm(-2) in continuous three years, a plot with the yield of 20 322 kg x hm(-2) (HF) was chosen to make comparison with the conventional farmland (CF) whose maize yield was 8920. 1 kg x hm(-2).

[Effects of increasing field temperature on photosynthetic characteristics of summer maize].

A field experiment was conducted to study the effects of increasing field temperature on the grain yield and photosynthetic characteristics of summer maize cultivars ND108 and YD13. The results showed that under increasing field temperature in the period from male tetrad to maturing stage, the grain yield of ND108 and YD13 decreased by 46.6% and 45.

[Soil nutrient leaching patterns in maize field under different fertilizations: an in situ study].

An in situ field experiment with lysimeter was conducted to study the effects of different fertilizations on the nutrient leaching loss from brown soil in the growth season of summer maize. The results showed that abundant rainfall and irrigation were the main factors affecting the leaching loss. The leaching amount was higher in the early growth period of summer maize, but decreased after then.

[Effects of weak light stress on grain yield and photosynthetic traits of maize].

Through shading at 0-14 days before pollination (S1), 1-14 days after pollination (S2), and 15-28 days after (S3) pollination, this paper studied the effects of weak light stress on the grain yield and photosynthetic traits of maize cultivars FY3 and TY2. The results showed that all treatments of shading induced a decreased grain yield, among which, treatment S1 had the largest decrement, and FY3 was more sensitive to the shading. Weak light stress made the time of maximum grain-filling (Tmax) appeared later, grain-filling slowed down, and mass accumulation decreased.

[Effects of high field temperature on summer maize grain yield and quality].

A field study with two summer maize cultivars ND108 and YD13 showed that increased field temperature (3 degrees C) at the stage from male tetrad to maturity had significant effects on their grain yield and quality. The grain yield of ND108 and YD13 decreased by 46.6% and 45.