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991.
Ningthoujam Sandhyarani Rajkumar Kishor Gurumayum Jitendra Sharma 《Journal of Crop Science and Biotechnology》2011,14(3):213-217
Acorus calamus is an important medicinal plant which has been used in Indian traditional medicine since time immemorial. Various bioactive
molecules, viz., acorin, α- and β-asarone, asaryldehyde, caryophylene, isoasarone, methylisoeugenol, and safrol have been isolated from this
plant. However, the use of this plant for medicinal purpose has been recently banned due to the high toxic property of β-asarone.
The triploid Acorus calamus is reported to be low in β-asarone content and thus found to be the ideal raw material for medicinal use. The present investigation
represents our finding for successful in vitro clonal propagation of the elite triploid accessions of Acorus calamus for mass propagation. In the dual-phase culture system consisting of agar-solidified Murashige and Skoog medium overlaid
by liquid fraction of the same medium, maximum multiple shoot induction was favored by supplementation of α-naphthaleneacetic
acid (0.5 mg L−1) and 6-benzylaminopurine (2.0 mg L−1). In vitro rooting of the microshoots was maximum in the medium supplemented with indolebutyric acid at 2.0 mg L−1. The well-rooted microshoots could be successfully hardened and transplanted in the field. This result can be reproduced
and is a viable protocol for successful clonal propagation of the seedless triploid Acorus calamus for conservation and sustainable development. 相似文献
992.
Olawale Mashood Aliyu Oluwayemisi Oluwatosin Adeigbe Joshua Adedokun Awopetu 《Journal of Crop Science and Biotechnology》2011,14(2):143-150
The problem of declining tree yield has led to an investigation into the effectiveness of foliar application of exogenous
hormones to improve flowering, fruit set, and fruit retention in cashew. Five exogenous hormones, one Gibberellic Acid (GA3) and four Auxins (IAA, IBA, NAA, and 2,4-D) at seven different rates of application (0 mg L−1, 10 mg L−1, 25 mg L−1, 50 mg L−1, 100 mg L−1, 250 mg L−1, and 500 mg L−1) were tested on six yield-related components of the two Brazilian cashew genotypes. This trial was a factorial split-split-plot
design with each treatment replicated five times within a tree and three replications (three trees) per genotype. Responses
varied significantly between exogenous hormones, concentrations and genotypes. The cashew plants used showed hormone-specific
and optimum concentration response patterns. Of the five exogenous hormones tested, GA3 was most effective as its application at 50–100 mg L−1 gave five-fold improvements in flowering (precocity and number of hermaphrodite flowers) and fruiting, and about 69% increase
in fruit retention ability and 25% in nut size. Panicles treated with GA3 also produced relatively bigger nuts compared to the untreated. Days to flowering was found to be hormone sensitive, while
production of hermaphrodite flowers, fruit set, and nut development tended to be concentration specific. The GA3 exhibited a broad concentration tolerance among the five exogenous hormones investigated. Our data showed that using GA3 at 50 mg L−1 will enhance flowering precocity, shorten flowering duration, increase production of hermaphrodite flowers and fruit set
significantly, and resultant nuts develop optimally with high percentage retention. Thus, it suggests cashew yield could be
increased by exogenous foliar application of GA3 at 50–100 mg L−1 at pre-blooming stage. 相似文献
993.
Mahipal S. Shekhawat Narpat S. Shekhawat Harish Kheta Ram Mahendra Phulwaria Amit Kumar Gupta 《Journal of Crop Science and Biotechnology》2011,14(2):133-137
An in vitro propagation method for female plants of Momordica dioica (Roxb.) has been established. The nodal segments were harvested and the cut ends of the explants were sealed with wax and
then surface sterilized and cultured. Bud breaking occurred on Murashige and Skoog’s (MS) agar-gelled medium + 2.0 mg L−1 6-Benzylaminopurine (BAP) + 0.1 mg L−1 Indole-3 acetic acid (IAA). The cultures were amplified by passages on MS medium supplemented with 1.0 mg L−1 BAP + 0.1 mg L−1 IAA. Further, shoot amplification (29.2 shoots per vessel) was achieved by subculturing of in vitro regenerated shoot clump on MS medium + 0.5 mg L−1 BAP + 0.1 mg L−1 IAA. The micropropagated shoots were subsequently transferred for root formation on half-strength MS medium + 2.0 mg L−1 Indole-3 butyric acid (IBA) with 89% success rate. The in vitro-regenerated shoots were also rooted ex vitro with 34% success. These plantlets were hardened in the greenhouse and transferred to the field. The established protocol
is suitable for true to type cloning of mature female plant of M. dioica. 相似文献
994.
Weixian Liu Moon Young Kim Kyujung Van Yeong-Ho Lee Hulin Li Xianhu Liu Suk-Ha Lee 《Journal of Crop Science and Biotechnology》2011,14(1):65-70
Two soybean recombinant inbred line populations, Jinpumkong 2 × SS2-2 (J × S) and Iksannamulkong × SS2-2 (I x S) showed population-specific
quantitative trait loci (QTLs) for days to flowering (DF) and days to maturity (DM) and these were closely correlated within
population. In the present study, we identified QTLs for six yield-related traits with simple sequence repeat markers, and
biological correlations between flowering traits and yield-related traits. The yield-related traits included plant height
(PH), node numbers of main stem (NNMS), pod numbers per plant (PNPP), seed numbers per pod (SNPP), 100-seed weight (SW), and
seed yield per plant (SYPP). Eighteen QTLs for six yield-related traits were detected on nine chromosomes (Chrs), containing
four QTLs for PH, two for NNMS, two for PNPP, three for SNPP, five for SW, and two for SYPP. Two highly significant QTLs for
PH and NNMS were identified on Chr 6 (LG C2) in both populations where the major flowering gene, E1, and two DF and DM QTLs were located. One other PNPP QTL was also located on this region, explaining 12.9% of phenotypic
variation. Other QTLs for yield-related traits showed population-specificity. Two significant SYPP QTLs potentially related
with QTLs for SNPP and PNPP were found on the same loci of Chrs 8 (Satt390) and 10 (Sat_108). Also, highly significant positive
phenotypic correlations (P < 0.01) were found between DF with PH, NNMS, PNPP, and SYPP in both populations, while flowering was negatively correlated
with SNPP and SW in the J × S (P < 0.05) and I × S (P < 0.01) populations. Similar results were also shown between DM and yield-related traits, except for one SW. These QTLs identified
may be useful for marker-assisted selection by soybean breeders. 相似文献
995.
Edak Aniedi Uyoh Ikootobong Sunday Urua Valentine Otang Ntui Elza Cletus Okpako 《Journal of Crop Science and Biotechnology》2011,14(4):227-232
Nuclear DNA of three accessions of Parkia biglobosa collected from three locations in northern Cross River State was investigated using a Patec PA II flow cytometer equipped
with an argon ion laser (488 nm), and pictures of mitotic chromosomes were taken using a digital micro-camera (Canon) placed
on the eye piece of a binocular microscope at 100X oil immersion. Metaphase chromosome counts of 2n = 22 for accessions A
and C and 2n = 24 for accession B, were obtained and through flow cytometry, the three accessions were confirmed to be diploids.
The nuclear DNA content and genome size for the accessions were 1.5085, 1.489, and 1.5266 pg (737.7054, 728.121, and 746.5074
Mbp) for accessions A, B, and C, respectively. In another experiment, leaf samples from greenhouse-germinated seeds were analyzed
for variation in the banding pattern of the protein by SDS-PAGE in the three accessions. Protein was resolved into three banding
groups according to their electrophoretic mobility: slow, medium, and fast, clustering between 100–200, 40–70, and 10–25 kDa,
respectively. There was 76% similarity in the banding pattern between the accessions. 相似文献
996.
Heavy doses of N fertilizers are commonly applied to green tea fields in Japan, and cause large amount of nitrate leaching
in ground water and emission of ammonia and nitrous oxide (N2O) to the atmosphere. The Denitrification and Decomposition (DNDC) model was tested against experimental data on N2O emissions from the tea field in Nishio, Aichi, Japan. There were reasonable agreements between the simulated and measured
values of N2O emissions for this site. The model was then applied for estimating the environmental impacts as affected by farm management
practices, climate change, and soil properties. The model results were assessed with respect to major indicators of agro-ecosystems
including crop yield, soil organic carbon sequestration, nitrate leaching loss, and N2O emission. The results indicated that use of compost significantly reduced nitrate leaching and N2O emissions in comparison with N fertilizer. When soil pH and texture shifted to non-acidic and coarser soil, N2O emission increased; and a change in temperature and precipitation affected N2O emission, nitrate leaching, and SOC sequestration. This study thus revealed the biogeochemistry model as a powerful tool
in addressing the complex efficacy of the alternative farm management practices in tea fields across various climate and soil
conditions. 相似文献
997.
Esakky Ramachandran Suchit Ashish John Gerard Abraham Partha Sarathi Bhattacharya 《Journal of Crop Science and Biotechnology》2011,14(4):275-279
The PTM3 (MADS-box) gene characterized from flower of Aspen was ectopically expressed in cotton and was found to result in desirable
agronomic traits. Among several transgenic lines, the PTM3 cotton event-10 was found to flower significantly earlier than
the control and yield better [Ramachandran et al. (2011)]. We report our findings on performance based on greenhouse evaluation
and inheritance of PTM3 cotton event-10. The T1 progeny of event-10 were grown in pots under RBD design. The progeny were confirmed by kanamycin imbibition test, PCR, and
GUS assay which showed the segregation of transgene at about 3:1 ratio. GUS assay was performed with pollen from all transgenic
plants; plants that expressed gus in all pollen versus those that showed segregation for expression were found to be at a
ratio of 1:2. Similar to observations made in the T0 generation of event-10, the agronomic evaluation of T1 progeny exhibited, on an average, earliness of 13 days in flowering, 13.5 days in crop maturity, and 22% of yield enhancement.
The T2 progeny of homozygous lines were grown on field soil in the greenhouse under strip trial design to see the effect as observed
from potted plants of T1 progeny. Inheritance of transgene cassette to T2 progeny was confirmed by the same tests used to analyze T1 progeny. As exhibited by T0 and T1 progenies, the T2 progeny also showed earliness of 8 days in flowering, 12 days in crop maturity, and 17% of yield enhancement. The data generated
from the progeny over two generations confirms that the PTM3 cotton event-10 is superior in agronomic characters as compared
to non-transgenic cotton and is of interest for breeding shorter duration varieties with improved yield. 相似文献
998.
Mi-Young Kang Catherine W. Rico Sang-Chul Lee 《Journal of Crop Science and Biotechnology》2011,14(2):111-118
The physicochemical properties of pigmented (Midorimochi, Jeokjinjubyeo, and Heukmichalbyeo) and non-pigmented (Hwayoungbyeo)
rice varieties were investigated. Starch from non-pigmented rice consisted mainly of large polyhedral granules that were more
loosely packed than those of the non-pigmented sample. Pigmented rice showed higher linoleic acid content (36–40%) and hydrolysis
rate (63–79%) but lower oleic acid content (35–39%), blue value (0.05–0.17), and viscosity values than the non-pigmented one.
Significantly higher mineral content, blue value, and pasting and viscosity values were observed in the Jeokjinjubyeo sample
compared to those of the other pigmented rice samples. The Midorimochi variety, on the other hand, exhibited the highest total
amino acid (816.82 ng mg−1) and sugar (0.15–3.35 μg g−1) contents and the lowest pasting and viscosity values. No substantial difference in the X-ray diffraction pattern was observed
among the samples. Results of this study could serve as baseline information for the quality evaluation of three pigmented
rice cultivars and provide a better understanding of their potential uses and food industry applications. 相似文献
999.
Canopy cover (CC) is a good predictor variable for plant growth parameters such as leaf area index and aboveground biomass.
A nondestructive, low-cost, and convenient method is presented for estimating CC using digital camera image analysis. CC was
estimated by the ratio of plant pixels to total pixels of digital camera image of rice field. To determine the criteria for
segmenting the rice plant from variable soil background, three mosaic images for rice plant, flooded/bare soil, and algae-infested
background were prepared from digital camera images that were taken in various field conditions. An image analysis program
was developed in Visual Basic to extract red, green, and blue (RGB) features from the mosaic images, calculate RGB-based color
indices, and compute the minimum segmentation error for separating rice plant from background. When judged by the segmentation
error, modified excessive green index (MEGI) showed the highest potential for segmenting rice plant from flooded/bare soil
background, followed by normalized green (g) and excessive green index (EGI). At the threshold MEGI value of 0.03, the segmentation
error was the lowest as 0.13%. Any single index considered was not satisfactory in segmenting rice plant from algae-infested
background. However, a discriminant function of 1.2553EGI + 0.01735G − 0.01474B was successful in segmenting rice plant from
flooded/bare soil and algaeinfested background with segmentation errors of 0.34 and 1.17%, respectively. CC for four rice
varieties from tillering to booting stage was estimated based on the threshold value of MEGI and discriminant function and
also manually using commercial software. Both estimates of CC showed good relationship of r2 = 0.94, suggesting that a digital camera could be used efficiently for measuring the CC of rice field. 相似文献
1000.
Hitoshi Fujiie Atsushi Maruyama Masako Fujiie Michiko Takagaki Douglas J. Merrey Masao Kikuchi 《Irrigation and Drainage Systems》2011,25(1):39-60
It is well-known that major irrigation projects have a strong scale economy, handicapping irrigation development in sub-Saharan
Africa (SSA) because of the difficulty in formulating large-scale projects. Using project-level investment cost and performance
data of major and minor irrigation projects, this paper examines the causes of the economy of scale phenomenon. We find that
strong scale economy exists not only for major but also for minor projects, i.e., small- and micro-scale, projects. This is
largely because of the existence of indivisible overhead costs such as high-opportunity-cost human resources for planning,
designing and engineering management and supervision. We also find that large differences between major and minor projects
in the absolute level of overhead as well as construction costs creates a strong scale diseconomy and results in better performance
of minor projects. The advantage of minor projects holds even when their higher risk associated with the water source is taken
into consideration. We argue that there is an urgent need to promote irrigation development in SSA through developing minor
projects, and to reduce the heavy burden of overhead costs by developing the capacity of human resources at the national,
local and farmer levels in the fields of irrigation engineering, irrigation agronomy, institutional development, and micro
water management technologies. 相似文献