Supervisor(s): Ministry of Agriculture Sponsor(s): Chinese Academy of Agricultural Sciences；Chinese Association of Agricultural Science Societies CN：11-1328/S
Scientia Agricultura Sinica, the 1st in Comprehensive Agricultural Science, is supervised by Ministry of Agriculture of PRC, and sponsored by Chinese Academy of Agricultural Sciences; Chinese Association of Agricultural Science Societies. Scientia Agricultura Sinica, launched in 1960, is a leading peer-reviewed and mufti-disciplinary journal and published semi-monthly in Chinese with English title, abstract, figures, tables and references. It aims to publish those papers that are influential and will significantly advance scientific understanding in agriculture fields worldwide. The scope covers Crop Genetics, Breeding, Germplasm Resources; Physiology, Biochemistry, Cultivation, Tillage Plant Protection; Soil & Fertilization, Agro-Ecology & Environment, Bio-energy; Animal Science, Veterinary Science, Agricultural Information Science; Food Science; Agricultural Economics and Management; Agricultural Sustainability.
The journal is included in JST, CA and CSCD.
Editor-in-Chief Wan Jianmin Associate Editor-in-Chief Zou Ruicang Tang HuaJun Wu Kongming Guo YuYuan Geng Xu Sun Tan Executive Editor Lu Wenru
[Objective] In previous work, we proven that a bZIP type transcription factor gene,
AtTGA4, could improve the drought resistance and low nitrogen tolerance of transgenic
Arabidopsis thaliana. In this study,
AtTGA4 was transformed into wheat to identify the tolerance of transgenic wheats to low phosphorus stress in field. At the same time, the physiological mechanism of
AtTGA4 gene to improve the stress resistance of transgenic wheats was analyzed, which laid a solid foundation for the molecular breeding of wheat tolerant to low phosphorus stress. [Method] Used particle bombardment method of minimal expression box to co-transform
AtTGA4 and marker gene
Bar into wheat variety Shi4056. After transformation, we screened many transgenic wheat lines without
Bar gene and with
AtTGA4 gene through PCR assay. In field experiment, basing on fertilizer nutrient content in soil, we applied different levels of phosphate, which led to low phosphorus stress in soil. The
AtTGA4 transgenic wheat lines were tested under low phosphorus. During the flowering stage, some physiological indexes were identified, such as efficiency of primary conversion of light energy of phoyosystem Ⅱ (Fv/Fm), the relative content of chlorophyll (SPAD), and canopy temperature depression (CTD) were investigated. At the mature stage, the agronomic traits such as plant height, tiller number, grains per spike were investigated, and some values such as the grain yield, phosphorus concentration, and phosphorus uptake in different components in wheat (root, stem, leaf and grain) were measured and data statistic analysis were completed. [Result] The PCR analysis showed that
AtTGA4 gene had been stablely inherited to the T
4 generation in Shi4056 and four stable transgenic lines were obtained. According to the results of soil nutrient content, 812.39 kg·hm
−2 of superphosphate was applied to normal plots, and no phosphorus was applied in low phosphorus treatment plots. The statistical results of yield and agronomic traits showed that the grain yield of
AtTGA4 transgenic lines L1 and L2 was increased compared with wild type (WT) significantly under normal condition and low phosphorus stress. Under the normal condition, the yield of transgenic wheat was increased by 5.3%–8.6%, and under low phosphorus stress, the grain yield of transgenic wheat was increased by 4.4%–7.7%. The thousand seed weight of
AtTGA4 transgenic wheat was significantly higher than that of the WT. The results of physiological index assay in field showed that the Fv/Fm and CTD of transgenic lines L1 and L2 were significantly better than those of WT under the condition of low phosphorus, while SPAD had no significant difference. We found that the WT under low phosphoru condition had their grain filling ended earlier than the transgenic wheat, and the ears turned yellow earlier for WT than the transgenic wheat plants. The phosphorus content assay at the late mature stage showed that the phosphorus concentration in the stems of L1 and L2 of transgenic lines increased significantly compared with that of WT under the condition of low phosphorus, but there was no significant difference in other tissues. Under the condition of low phosphorus, the total phosphorus contents in stems, leaves, and grains of two transgenic lines were higher than those of WT, and the total phosphorus content in the aerial part was increased by 6.38%–17.47%. The qRT-PCR results of
AtTGA4 in transgenic wheat showed that the expression of
AtTGA4 in Line 2 (L1) was 0.69 times that of Line 1 (L1). [Conclusion] The above results showed that under the condition of low phosphorus stress,
AtTGA4 could improve the uptake and transportation of phosphorus in transgenic wheat plants, increase the yield of transgenic plants, and further enhance the tolerance of transgenic wheat to low phosphorus stress.
[Objective] The aim of this study was to clone the full length of P450 family
CYP79F1 gene from broccoli, investigate its sequence characteristic, and analyze its expression and correlation with sulforaphane content in different developmental broccoli organs. These findings will provide a scientific basis for further revealing the mechanism of sulforaphane metabolism in broccoli and lay a practical foundation for the genetic improvement and breeding of broccoli varieties. [Method] The full-length sequence of
CYP79F1 gene was obtained by RACE cloning (5′ and 3′). According to the software of DNAMAN 6.0, gene splicing, amino acid sequence analysis and protein secondary structure prediction of
CYP79F1 gene were carried out, and at the same time, bioinformatics information was also predicted by online program and software. The quantitative real-time PCR (qRT-PCR) method was used to study the expression of
CYP79F1 gene in different developmental organs of broccoli. The sulforaphane contents of different developmental organs were detected with high performance liquid chromatography (HPLC) method, and they were roots, stems, leaves, developmental buds at bolting stage (top buds, mature buds, buds one day before flowering and flowers), and seeds. Pearson’s correlation analysis was carried out by the software SPSS 10.0. [Result] The full-length sequence of
CYP79F1 gene was cloned, and the gene of
CYP79F1 was 2 014 bp in length, containing a 1-620 bp opening reading frame (ORF) and encoding a polypeptide of 540 amino acids. They shared over 95% identity with the homologous proteins from
Brassica plants, such as cabbage, Chinese cabbage, Chinese kale and rape. The bioinformatics analysis showed that the CYP79F1 protein was hydrophilic protein with two signal-peptides and two transmembrane regions, and the Wolf Psort protection indicated that they were located in the cytoplasm. The expression of
CYP79F1 gene was high in the roots and the stems, and the lowest in the leaves. During developmental stage of buds, the expression of
CYP79F1 gene was up-regulated at the early stages (young buds), and then decreased (mature buds to flowers). There was no significant difference in gene expression between roots, stems, leaves, developmental buds at bolting stage and seeds. The correlation analysis showed that the expression level of
CYP79F1 gene showed an extremely significant positive correlation with sulforaphane content in developmental buds at bolting stage (
R = 0.96,
P < 0.05), and the expression of
CYP79F1 gene might influence the generation of sulforahane in different organs of broccoli, especially in developmental buds. [Conclusion] The
CYP79F1 gene was comprehensively obtained and characterized from broccoli and CYP79F1 may play an important role in sulforaphane metabolism and revealing the diversity of sulforaphane content in different organs of broccoli.
[Objective] In order to provide a basis for promoting soil fertility, increasing crop yield, and reducing non-point source pollution for rotation of winter wheat and summer maize in North China Plain, it is necessary to study the effect of long-term additional application of organic manure/straw incorporation on crop yield and soil nitrogen leaching risk. [Method] With the 27-year long-term fertilizer experiment in fluvo-aquic soil in Changping District, Beijing, China as the research platform, five treatments were set up, including namely control (CK), chemical fertilizers (NPK), NPK + organic manure (NPKM), NPK + 50% more organic manure (NPKM+) and NPK + straw incorporation (NPKS). Then, crop yield of wheat and maize, soil fertility, nitrogen leaching risk, and soil nitrogen distribution characteristics under different fertilization treatments were analyzed. [Result] Results showed that (1) long-term additional application of organic manure or straw incorporation could increase crop yield and improve soil fertility during the past 27 years. Among these different fertilizer treatments, additional application of organic manure was particularly excellent. Compared with NPK, the yield of wheat and maize could increase by 41%–50% and 30%–32% under NPKM and NPKM+ treatments, respectively. Meanwhile, NPKM and NPKM+ treatments could increase soil organic carbon (SOC) and total nitrogen (TN) in 0–20 cm depth by 62%–121% and 107%–187%, respectively. However, the partial factor productivity (PFP
N) in wheat and maize season was reduced by 22%–32% and 27%–41%, respectively. Contrarily, the effect of straw incorporation on yield enhancement and soil nutrient improvement was lower than that of additional application of organic manure. The yield of wheat and maize and content of SOC and TN were increased by 24%, 6%, 9%, and 97% under straw incorporation, respectively, compared with NPK. However, the PFP
N in wheat season was increased by 216% while was reduced by 40% in maize season. (2) SOC, TN, nitrate nitrogen (NO
3−-N), soil dissolved organic carbon, soil dissolved organic nitrogen content and the microbiological processes of soil nitrogen mineralization rate and nitrification potential in 0–20 cm soil depth were all higher than that of 20–200 cm soil depth, which indicated that the effect of long-term additional application of organic manure or straw incorporation on soil nutrients and microbiological processes mainly occurred in the surface soil. Compared with NPK, NPKM treatment could significantly increase NO
3−-N content in the 100–200 cm soil depth and the average value of NO
3−-N was 17.8–26.1 mg·kg
−1. NPKS treatment could increase soil NO
3−-N content in the 0–100 cm soil depth to some extent and the average content of NO
3−-N was 3.6–13.4 mg·kg
−1. This indicated that additional application of organic manure could promote the downward migration of soil NO
3−-N and straw incorporation could retain soil NO
3−-N. As introducing additional nitrogen from manure or straw, the nitrogen surplus was increased by 312%, 1 037%, and 953% in NPKM, NPKM+, NPKS treatments compared with NPK treatment, suggesting a relatively high nitrogen leaching risk. [Conclusion] Based on the conventional fertilization, long-term additional application of organic manure and straw incorporation could increase crop yield and soil fertility, but also promote soil nitrogen surplus and nitrogen leaching risk. Especially, long-term additional application organic manure could increase nitrogen leaching risk.
[Objective] The objective of this study is to evaluate the leaf nutritional status by investigating the mineral elements content in the leaves of Powell navel orange orchard at flowering stage in Jiangjin and Fengjie regions of Chongqing in the Three Gorges Reservoir Area, and to provide a basis for formulating the fertilization scheme of Powell navel orange. [Method] Field experiments were conducted in forty representative 12-year-old Powell navel orange plots from Jiangjin and Fengjie regions in Chongqing Three Gorges Reservoir Area. The plot yield and contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), manganese (Mn), zinc (Zn) were measured. The compositional nutrient diagnosis (CND), diagnosis and recommendation integrated system (DRIS), and deviation from optimum percentage (DOP) methods were used to diagnose the leaf nutritional status for the low yield groups. [Result] The leaf analysis of CND indicated that the yield cutoff value of high-yield orchard was 330 t·hm
−2, and only six plots from Fengjie fulfilled this criterion, accounting for 15.0% of 40 plots. The optimum values of leaf nutrition at flowering stage were N (2.0 ± 0.1)%, P (0.12 ± 0.01)%, K (2.1 ± 0.5)%, Ca (3.1 ± 0.4) g·kg
−1 DW, Mg (0.31 ± 0.03) g·kg
−1 DW, Fe (36.6 ± 13.1) mg·kg
−1 DW, Mn (51.4 ± 21.6) mg·kg
−1 DW, Cu (2.2 ± 0.7) mg·kg
−1 DW and Zn (12.3 ± 1.5) mg·kg
−1 DW according to the leaf nutrition concentration in Fengjie high yield group. The CND norms were established as V
N* = 3.62 ± 0.07, V
P* = 0.78 ± 0.08, V
K* = 1.36 ± 0.21, V
Ca* = 1.74 ± 0.14, V
Mg* = −0.55 ± 0.10, V
Fe* = −2.74 ± 0.36, V
Mn* = −2.40 ± 0.39, V
Cu* = −5.55 ± 0.32, V
Zn* = −3.78 ± 0.10, respectively. Meanwhile, there were 30 (N/K, N/Fe, N/Cu, P/K, P/Fe, P/Cu, K/Fe, K/Cu, Ca/N, Ca/P, Ca/K, Ca/Fe, Ca/Mn, Ca/Cu, Mg/N, Mg/P, Mg/K, Mg/Fe, Mg/Cu, Mn/N, Mn/P, Mn/K, Mn/Mg, Mn/Fe, Mn/Cu, Mn/Zn, Zn/Ca, Zn/Mg, Zn/Fe, Zn/Cu) and 14 (Ca/K, Mg/K, Mg/Zn, Mn/N, Mn/P, Mn/K, Mn/Ca, Mn/Mg, Mn/Fe, Mn/Cu, Cu/P, Cu/K, Cu/Mg, Cu/Fe) important DRIS norms in Jiangjin and Fengjie regions by DRIS method, respectively. Moreover, CND, DRIS, and DOP were used for the leaf nutrition diagnosis in producing the low-yield subpopulation of Fengjie plots and Jiangjin region. Among them, the fertilization order was confirmed as Ca > Mg > N > P > Mn in Jiangjin region and N > Ca > P > Zn > Fe > Mn in Fengjie region by CND method; Ca > Mg >> Mn > N > P in Jiangjin region and Zn >> Fe > Ca > Mn > N > Mg in Fengjie region by DRIS method; Ca > Mn > Mg in Jiangjin region and Mn >> Zn > Fe > Ca > Mg > N in Fengjie region by DOP method. [Conclusion] The average nutrient balance indexes of CND, DRIS and DOP were 166.5, 4 291.0, and 117.5 in Jiangjin region, respectively. The average nutrient balance indexes of CND, DRIS and DOP were 37.2, 570.0, and 14.1 in Fengjie region, respectively. The leaf nutritional status in Fengjie region was superior to that in Jiangjin region, and both areas had a great potential of production.
[Objective] To identify the genotypes with high photosynthesis capacity and to optimize methods for further screening, genetic variations of photosynthetic gas exchange parameters among exotic sugarcane cultivars was investigated. [Method] Using a LI-6400 portable photosynthesis system, gas exchange measurements were conducted on the youngest fully-expanded leaves of 50 cultivars introduced from abroad at their grand-growth stage. Six parameters were measured, namely photosynthesis (
A), stomatal conductance (
gs), intercellular CO
2 concentration (
Ci), transpiration rate (
E), intrinsic water use efficiency (
WUEintr), and instantaneous water use efficiency (
WUEinst). Key statistics were determined including broad sense heritability, correlations among parameters. Besides, the variation in responses among cultivars was characterized using principal component analysis, while cluster and discriminant analysis were conducted for elite screening. [Result] Significant genetic variation was found for every parameter, with the order (highest to lowest variation) being
gs,
A,
E,
Ci,
WUEintr, to
WUEinst. The broad heritability was high (> 70%) for all parameters except
WUEinst (which was 58.8%). There were significant correlations between all the parameters except that between
WUEinst and
E. Stomatal conductance had strong nonlinear relationships with other parameters, consistent with its pivotal role in regulating leaf gas exchange. Two principal components were extracted through principal component analysis, which could be interpreted as being predominately related to “carbon assimilation” and “water use efficiency”, respectively. These two components varied independently among the clones, indicating the possibility of screening for elites harboring both high carbon assimilation and high water use efficiency. The cluster analysis identified a group of six genotypes which had both high carbon assimilation and water use efficiency. [Conclusion] Significant variation due to genetic differences in gas exchange parameters exists among exotic sugarcane cultivars. An elite group of cultivars with both high carbon assimilation and water use efficiency were identified, including B4362, B51-410, US67-22, BH10-12, C323-87, and Co685. The methods to optimize large-scale screening in sugarcane breeding programs for favorable photosynthetic capacity were also determined and discussed.
