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1.
Protein content, which represents rice taste quality, must be estimated in order to create a harvesting plan as well as next year’s basal dressing fertilizer application plan. Ground-based hyperspectral imaging with high resolution (1 × 1 mm per pixel) was used for estimating the protein content of brown rice before harvest. This paper compares the estimation accuracy of rice protein content estimation models generated from the mean reflectances of five regions of interest (ROIs): the overall target area, dark area (less illuminated parts of the rice plants), canopy area (leaves, yellow leaves, and ears), leaf area, and ear and yellow leaf area. The size of the target sampling area was 0.85 × 0.85 m. An R + G + B histogram and a GNDVI–NDVI image were used to separate the target area into the individual ROIs. The values of the coefficient of determination R 2 and the root mean square error of prediction (RMSE) were similar for each model: R 2 ranged from 0.83 to 0.86 and RMSE ranged from 0.27 to 0.30% for all models except for the dark area model, where R 2 = 0.76 and RMSE = 0.35%. There were no significant differences in the magnitude of the estimation error among all models. This result indicates that it is not necessary to obtain an image with a ground resolution that is greater than 0.85 × 0.85 m per pixel to estimate rice protein content before harvest. This result should provide useful information when deciding the altitude of platforms for imaging rice fields.  相似文献   

2.
Easy-to-capture and robust plant status indicators are important factors when implementing precision agriculture techniques on fields. In this study, aerial red, green and blue color space (RGB) photography and near-infrared (NIR) photography was performed on an experimental field site with nine different cover crops. A lightweight unmanned aerial system (UAS) served as platform, consumer cameras as sensors. Photos were photogrammetrically processed to orthophotos and digital surface models (DSMs). In a first validation step, the spatial precision of RGB orthophotos (x and y, ± 0.1 m) and DSMs (z, ± 0.1 m) was determined. Then, canopy cover (CC), plant height (PH), normalized differenced vegetation index (NDVI), red edge inflection point (REIP), and green red vegetation index (GRVI) were extracted. In a second validation step, the PHs derived from the DSMs were compared with ground truth ruler measurements. A strong linear relationship was observed (R 2 = 0.80?0.84). Finally, destructive biomass samples were taken and compared with the remotely-sensed characteristics. Biomass correlated best with plant height (PH), and good approximations with linear regressions were found (R 2 = 0.74 for four selected species, R 2 = 0.58 for all nine species). CC and the vegetation indices (VIs) showed less significant and less strong overall correlations, but performed well for certain species. It is therefore evident that the use of DSM-based PHs provides a feasible approach to a species-independent non-destructive biomass determination, where the performance of VIs is more species-dependent.  相似文献   

3.
Genotyping for locus PGR (progesterone receptor gene) of the Holstein servicing bulls (World Wide Sires) was carried out. The frequencies of alleles and genotypes of this locus are given. Significant (P < 0.05) superiority of the homozygous genotype AA of locus PGR was found in relation to the heterozygous genotype AG for several economically valuable traits: PTAM (predicted transmitting ability for milk, 380 points), PL (productive life, by 1.3 months), and FE (feed cost–feeding efficiency index, 37 points). Significant superiority (P < 0.05) of the homozygous genotype GG over the heterozygous genotype AG for the PL trait was also found, by 1.2 months. The obtained data can be used for marker-dependent breeding.  相似文献   

4.
5.
Seven microsatellite loci were evaluated to compare the allele pool of Primorsky honeybee population (n = 90), which was introduced into the Novosibirsk region (south-western Siberia), with the populations of Middle Russian (n = 191, A.m. mellifera), Mountain Grey Caucasian (n =113, A.m. caucasica), Carniolan (n = 61, A.m. carnica) and Carpathian (n = 184, A.m. carpatica) races. The degree of genetic differentiation in Novosibirsk population using a variety of criteria (Fst, Rst (AMOVA), Nei genetic distances) was evaluated.  相似文献   

6.
Assessment of crop health status in real time could provide reliable and useful information for making effective and efficient management decisions regarding the appropriate time and method to control crop diseases and insect damage. In this study, hyperspectral reflectance of symptomatic and asymptomatic rice leaves infected by Pyricularia grisea Sacc, Bipolaris oryzae Shoem, Aphelenchoides besseyi Christie and Cnaphalocrocis medinalis Guen was measured in a laboratory within the 350–2?500 nm spectral region. Principal component analysis was performed to obtain the principal component spectra (PCs) of different transformations of the original spectra, including original (R), common logarithm of reciprocal (lg (1/R)), and the first derivative of original and common logarithm of reciprocal spectra (R′ and (lg (1/R))′). A probabilistic neural network classifier was applied to discriminate the symptomatic rice leaves from asymptomatic ones with the front PCs. For identifying symptomatic and asymptomatic rice leaves, the mean overall discrimination accuracies for R, lg (1/R), R′ and (lg (1/R))′ were 91.3, 93.1, 92.3 and 92%, and the mean Kappa coefficients were 0.771, 0.835, 0.829 and 0.82, respectively. To discriminate between disease and insect damage, the overall accuracies for R, lg (1/R), R′ and (lg (1/R))′ were 97.7, 98.1, 100 and 100%, and the Kappa coefficients were 0.962, 0.97, 1 and 1, respectively. These results demonstrated that hyperspectral remote sensing can discriminate between multiple diseases and the insect damage of rice leaves under laboratory conditions.  相似文献   

7.
The recognition of apple fruits in plastic bags is easy to be affected by reflected and refracted light. In order to weaken the influence of light, a method based on block classification is proposed. The method adopts watershed algorithm to segment original images into irregular blocks based on edge detection results of RG grayscale images firstly. Compared with the watershed algorithm based on gradient images, the segmentation method can preserve fruits edge and reduce the number of blocks by 20.31%, because graying image method, RG, filters most of leaves and edge detection operator insures that the edge of fruits are detected accurately. Next, these blocks are classified into fruit blocks and non-fruit blocks by support vector machine on the basis of the color and texture features extracted from blocks. Compared with the image recognition method based on pixel classification, the proposed method can restrain the interference of light caused by plastic bags effectively. The false negative rate (FNR) and false positive rate (FPR) of the method based on pixel classification are 21.71 and 14.53% respectively. The FNR and FPR of the proposed method are 4.65 and 3.50% respectively.  相似文献   

8.
9.
The agronomic characteristics of different legume cover crops and their effects on soil chemical properties were investigated in a short-term field study. We compared weed biomass, nitrogen equivalence, growth rate, leaf chlorophyll content, cover crop biomass, soil total organic carbon, and soil total nitrogen under eight different legume cover crops in a short-term field experiment. We found the highest growth rate, cover crop dry biomass, N plant content, and N contribution with C. ochroleuca plants, whereas for leaf chlorophyll content, soil organic carbon, and total nitrogen the highest values were found with M. pruriens. We did not find any significant difference among C. ochroleuca and M. pruriens for cover crop dry biomass. Our findings suggest that the incorporation of cover crops into the soil can change positively the soil chemical properties, such as soil organic carbon and total nitrogen. Our results also highlight the importance of considering the short-term effect of cover crops on the tropical soil fertility maintenance, in this case, Regosol.  相似文献   

10.
Inexpensive, accurate, and rapid measurements of sodicity are required to identify the restoration options for degraded sites. This study determined the spatial variability of the percent of ammonium acetate extractable Na (%Na), apparent electrical conductivity (ECa), pH1:1, elevation and topographic wetness index, and used this information to create %Na management zones. In an 8.1 ha North Dakota field that contained Natraquolls and Calciaquolls, 1088 soil samples from the 0–0.3 and 0.3–0.6 m were collected from a 12.2 by 12.2 m geo-referenced grid. At each grid point, the elevation and ECa was determined using a differential corrected global positioning system and EM38m, respectively. Soil samples were analyzed for the %Na, EC1:1, pH1:1, and soil dispersion. Exponential semi-variogram models explained 96.7% of the ln-transformed %Na data in the 0–0.3 m soil depth, and %Na was correlated to EC1:1 (r = 0.54), pH1:1 (r = 0.68), clay dispersion (r = 0.68), ECav (r = 0.49), and ECah (r = 0.57). Forward stepwise regression models based on elevation, EC1:1, pH1:1, and ECah explained 64 and 74% of the %Na variability in the surface 0.3 m and subsurface 0.3–0.6 m, respectively. Management zones were identified that reduced the %Na variability up to 82%.  相似文献   

11.
The results of molecular genetic analysis of wild species and varieties of genus Malus Mill. for loci of monogenic scab resistance are presented. Dominant allele of gene Rvi6 was identified in varieties of M. robusta 43199, M. hupehensis, and M. floribunda. Locus Rvi4 was detected in genotypes of M. robusta v. persicifolia, M. asiatica 2343, M. sieversii 13280, M. niedzwetzkyana 13279, M. purpurea 2392, M. orientalis 41623, M. orientalis 29476, M. orientalis 29 460, M. spectabilis v. albi plena, and M. spectabilis v. rubra plena. Gene Rvi5 in the test collection of wild species is absent.  相似文献   

12.
The species composition of fungi from the genus Fusarium was studied, and the frequency of occurrence on cereals was determined. Populations of Fusarium spp. were represented by widespread species F. culmorum, F. heterosporum, F. sporotrichioides, F. oxysporum, F. nivale, F. graminearum, F. avenacеum, F. gibbosum, F. sambucinum, F. moniliforme, etc. The dynamics and frequency of occurrence of Fusarium spp. has made it possible to characterize the state of the species of fungi in a wide range of climatic areas of cereal cultivation in the Russian regions. The prevalence of the genus Fusarium was caused by the cultivars’ susceptibility to micromycetes. The frequency of occurrence of Fusarium species isolated from roots was steady, and, on the ears, it depended on the influence of weather conditions during the growing season of plants. The study of the intraspecific variability of fungi from the genus Fusarium has revealed a significant difference in signs of toxicity and pathogenicity depending on biotic and abiotic factors. More than 50% of strains from the genus Fusarium possessed low pathogenicity but had severe toxicity to wheat seedlings. Most strains of F. sporotrichiodes, F. culmorum, and F. sambucinum were highly pathogenic (from 36.4 to 55.6%) and toxic (from 55.6 to 81.3%). High adaptability to preservation in the soil and on the roots of weeds and crop residues of most crops expressing pathogenic and toxic activity was conductive to the widespread Fusarium spp.  相似文献   

13.
The Syntermes genus, the most significant termite pest in eucalyptus cultivation, damages roots and debarks plant rings. This can kill the seedlings of this plant, and thus require replanting. Integrated management, based on sampling plans can reduce damage to eucalyptus seedlings and allows the rational use of chemical control. The objectives were to model the spatial distribution of the Syntermes spp. foraging holes using the Matérn-cluster point process in the Cerrado region (Brazilian savannah), simulate a sampling plan for termite hole density, produce maps of foraging hole densities using geostatistics and validate the simulated sampling plan in the field. The distribution of the Syntermes spp. foraging holes was spatially non-homogeneous and it adjusted to the Matérn-cluster point process model in the Minas Gerais Cerrado areas. The best Syntermes sampling plan simulation in the area of Cerrado is to launch a circular 5 m radius parcel every 100 m (sampling error <5 %) in a systematic manner. The approach of point processes, combined with geostatistics, is adequate to produce maps for the termite Syntermes spp. infestation in the eucalyptus plantation.  相似文献   

14.
This paper presents history and ways of creating triploid apple cultivars differing from common diploid ones by less pronounced fruiting periodicity by years, higher marketability and weight of fruits, and self-fertility. In the search for an effective method of mass production of triploid seedlings, crosses of the type 4x × 4x, 4x × 3x, 4x × 2x, 3x × 4x, 3x × 3x, 3x × 2x, 2x × 4x, and 2x × 3x were studied. The most effective way of mass production of triploid seedlings was the 2x × 4x cross (diploid × tetraploid). In the group of 2x × 4x crosses, more than 9000 seedlings from different families were subjected to cytological analysis. The ratio of hybrid progeny in terms of ploidy levels was as follows: 30.3% diploids, 69.5% triploids, 0.2% tetraploids, and 0.04% aneuploids. It was established that triploids can also be obtained in 4x × 2x crosses; however, it is necessary to castrate the flowers in the maternal parent, since all apple tetraploids have high self-fertility. For the first time in the world, a series of triploid cultivars (approximately 20) was obtained from intervalent crosses of the diploid × tetraploid type in the All-Russia Research Institute of Fruit Crop Selection. Particularly interesting are triploid cultivars that have immunity to scab, which include nine cultivars, of which Aleksandr Boiko, Vavilovskoe, Maslovskoe, and Yablochnyi Spas are included in the State Register of breeding achievements allowed for use.  相似文献   

15.
16.
The aim of this paper is to study effects of GH and DGAT1 gene polymorphisms on feeding qualities of Hereford and Limousin bull calves bred in conditions of the Cis-Ural steppe zone. SNPs of genes GH and DGAT1 are investigated by polymerase chain reaction (PCR) and DNA restriction fragment length polymorphism (RFLP). The studied population of animals was assessed by defining the allele frequency and animal genotype occurrence for the studied gene SNPs, indicators of the actual and expected heterozygosity, and Pearson’s test. A study of polymorphism C214G of gene GH revealed that genotype LL prevails in Hereford and Limousin animals, 47.37 and 57.7%, respectively, while frequency of allele L is higher in Limousin bull calves (0.731). A study of polymorphism K232A of gene DGAT1 gene in both the populations showed absence of genotypes AA, which can be related to the low number of the studied animals. Expected heterozygosity indicators of gene GH are higher than the observed ones, and the observed heterozygosity is higher for DGAT1. The number of efficient alleles for the studied genes is higher for Hereford bull calves. In general, according to Pearson’s test, both the studied populations are in equilibrium. There is a significant effect of GH gene polymorphism on live weight gain rates at the end of sagination and total and average daily weight gains during animal raising.  相似文献   

17.
The persistence, and international expansion, of food banks as a non-governmental response to households experiencing food insecurity has been decried as an indicator of unacceptable levels of poverty in the countries in which they operate. In 1998, Poppendieck published a book, Sweet charity: emergency food and the end of entitlement, which has endured as an influential critique of food banks. Sweet charity‘s food bank critique is succinctly synthesized as encompassing seven deadly “ins” (1) inaccessibility, (2) inadequacy, (3) inappropriateness, (4) indignity, (5) inefficiency, (6) insufficiency, and (7) instability. The purpose of this paper is to examine if and how the contemporary food bank critique differs from Sweet charity’s “ins” as a strategy for the formulation of synthesizing arguments for policy advocacy. We used critical interpretive synthesis methodology to identify relationships within and/or between existing critiques in the peer-reviewed literature as a means to create “‘synthetic constructs’ (new constructs generated through synthesis)” of circulating critiques. We analyzed 33 articles on food banks published since Sweet charity, with the “ins” as a starting point for coding. We found that the list of original “ins” related primarily to food bank operations has been consolidated over time. We found additional “ins” that extend the food bank critique beyond operations (ineffectiveness, inequality, institutionalization, invalidation of entitlements, invisibility). No synthetic construct emerged linking the critique of operational challenges facing food banks with one that suggests that food banks may be perpetuating inequity, posing a challenge for mutually supportive policy advocacy.  相似文献   

18.
Genotyping of the leptin gene locus (LEP) (SNP: R25C, Y7F, and A80V) has been performed in the animals from two groups in the Holstein cattle herd. Groups 1 and 2 included the fourth to seventh lactation cows and the heifers, respectively. The objective of the surveys was to study the Holstein cattle polymorphisms of the leptin gene associated with the productive longevity according to the related literature data. It has been ascertained that the LEP gene (SNP: R25C, Y7F, and A80V) polymorphism in the Holstein animals determines the certain breed characteristics that can be used for introduction to marker assisted selection. (Particularly, a low (0.04–0.15) frequency of occurrence of the F allele is typical for the LEP-Y7F SNP; as for SNP LEP-A80V, a low frequency of occurrence (0–0.14) is typical for the homozygous animals with the VV genotype when compared to a rather high frequency of occurrence (0.36–0.45) in the heterozygous animals).  相似文献   

19.
The present studies have shown Laurus nobilis L. to be a drought tolerant species. When the plant was first subjected to dehydration, the rate of net photosynthesis decreased from Pn = (8–10) to –1 μmol/(m2 s) and to –3 μmol/(m2 s) during the second dehydration before it was subsequently irrigated. The rewatering on August 5 and August 8 promoted a sharp burst of this parameter, but the Pn value was restored to its original level only after August 8. Soil drought caused a drop in a rate of transpiration from 65–70 to 10 mg/(m2 s). Watering soil up to a 15% moisture level brought an increase in E = 25 mg/(m2 s), but only the second watering managed to fully restore it to the initial value. Apical growth of the plants was closely correlated with soil moisture. As the soil moisture was reduced to W = 15–5%, the terminal growth reached a saturation point and started to plateau. Watering the soil up to W = 15% promoted apical growth by 4 mm. Reducing soil moisture to W = 3–4% caused a complete cessation of the growth. Subsequent watering to W = 27–28% led to a gradual and complete recovery of turgor and an increase in the growth rate up to 6–8 mm per day. The surface response functions Pn = f(I, W) and E = f(I, W) allowed us to determine conditions and levels of potential maximums and boundaries of the areas of optimum photosynthesis and transpiration: optimum Pn = 8–9 μmol/(m2 s) with I = 900–1400 μmol/(m2 s) and W = 17–24% and the optimum E = 25–35 mg/(m2 s) with I = 1000–1400 μmol/(m2 s) and W = 16–24%.  相似文献   

20.
In the present study, 39 endophytic bacteria were isolated from different crops with main focus on maize roots and seeds. Endophytes were screened for drought stress tolerance, plant growth promoting (PGP) traits and antifungal activity. Out of 39 isolates, 32 could show drought tolerance up to–1.02 matric potential (MPa) and exhibited most of the plant growth promoting traits. But, only five isolates could show antagonistic activity against plant fungal pathogens. Based on the results, 10 promising isolates namely FTR, NFTR, FMZR9, FMZR2, MZ30V92, MRC12, MRC31, MRC33, MRC41 and MRR2 were selected and identified using biochemical and 16S rDNA gene sequencing as Pseudomonas aeruginosa (strains FTR and NFTR), Pseudomonas monteilii (strain FMZR2), Pseudomonas putida (strain FMZR9), Acitenobacter brumalii (strain MZ30V92), Enterobacter asburiae (strain MRC12), Sinorhizobium meliloti (strain MRC31), Pseudomonas thivervalensis (strain MRC33), Pseudomonas fulva (strain MRC41), and Pseudomonas lini (strain MRR2). Further, at–1.02 MPa all the 10 isolates showed PGP traits, and 3 isolates (FTR, NFTR and MRC12) showed antifungal activity. Thus, indicating that drought tolerant plant growth promoting antagonistic endophytic bacteria (PGPAE) helps in plant growth and disease management under drought stress.  相似文献   

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