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Seed viability monitoring is very important in ex situ germplasm preservation to detect germplasm deterioration. This requires seed-, time- and labor- saving methods with high precision to assess seed germination as viability. Although the current non-invasive, rapid, sensing methods (NRSs) are time- and labor-saving, they lack the precision and simplicity which are the virtues of traditional germination. Moreover, they consume a considerable amount of seeds to adjust sensed signals to germination percentage, which disregards the seed-saving objective. This becomes particularly severe for rare or endangered species whose seeds are already scarce. Here we propose a new method that is precise, low-invasive, simple, and quick, which involves analyzing the pattern of dehiscence (seed coat rupture), followed by embryonic protrusion.
ResultsDehiscence proved simple to identify. After the trial of 20 treatments from 3 rice varieties, we recognized that dehiscence percentage at the 48th hour of germination (D(48)) correlates significantly with germination rate for tested seed lots. In addition, we found that the final germination percentage corresponded to D(48) plus 5. More than 70% of the seeds survived post-dehiscence desiccation for storage. Hydrogen peroxide (1 mM) as the solution for imbibition could further improve the survival. The method also worked quicker than tetrazolium which is honored as a fast, traditional method, in detecting less vigorous but viable seeds.
ConclusionWe demonstrated the comprehensive virtues of dehiscence method in assessing rice seed: it is more precise and easier to use than NRSs and is faster and more seed-saving than traditional methods. We anticipate modifications including artificial intelligence to extend our method to increasingly diverse circumstances and species.
相似文献Fungal toxins in feed are leading issue in poultry industry causing a detrimental effect on the performance and health of poultry. The study was carried out to determine the incidence and concentration of the aflatoxins and their major producer Aspergillus flavus in home mix layer poultry feed in respect of seasonal variation throughout the year. A total of (n?= 204) home mix poultry layer feed samples were analyzed for the isolation of fungi. The isolates were initially screened through colony morphology and microscopic examination. However, aflatoxin concentration was determined by ELISA. Revealed results indicated that, the highest percentage of A. flavus was found during the months of June to August 50/54 (92.5%) followed by September to November 43/65 (66.1%), March to May 21/40 (52.5%), and December to February 18/45 (40%). As a whole, the incidence was recorded 132/204 (64.7%). Moreover, of the 132 samples, 41 (31%) were exceeded in respect of aflatoxin contamination from the legal limit (20 μg/kg) imposed by Food Drug Association (FDA). Statistically, the growth of A. flavus and aflatoxin production was found significantly different in respect of seasonal variation. As highest total viable fungal count (9.9?×?104 CFU/g) and aflatoxin level (72.27 μg/kg) were recorded during the months of June to August and lowest in December to February. Consequently, instantaneous essential control measures are demanded regarding appropriate storage and adequate drying in post-harvesting season. Along with surveillance plans and austere regulations for monitoring the aflatoxin contents for the wellbeing of consumers.
相似文献The aim of this study was to determine the prevalence, serological diversity, and virulence of Dichelobacter nodosus in footrot lesions of sheep and identification of its predominant serotype as a potential vaccine candidate. The overall prevalence of footrot in sheep was 16.19%, and ranged from 13.69 to 19.71%, respectively. A total of 759 flocks with 22,698 sheep were investigated for footrot and 2374 clinical samples were collected from naturally infected sheep exhibiting footrot lesions. Of the 2374 samples collected, 1446 (60.90%) were positive for D. nodosus by polymerase chain reaction (PCR). These positive samples when subjected to serogroup-specific multiplex PCR, 1337 (92.46%) samples carried serogroup B, 247 (17.08%) possessed serogroup E, 86 (5.94%) serogroup I, and one (0.069%) serogroup G of D. nodosus. While mixed infection of serogroups B and E was detected in 127 (8.78%), B and I in 46 (3.18%) and B, E, and I in 26 (1.79%) samples, respectively. The serogroup B of D. nodosus was the predominant (92.47%) serogroup affecting sheep population with footrot followed by serogroup E (19.91%) and serogroup I (4.57%), respectively. Virulent status of D. nodosus strains were confirmed by presence of virulence-specific integrase A (intA) gene and the production of thermostable proteases. The intA gene was detected in 709 (72.79%) samples while gelatin gel test carried out on 246 representative isolates all positive for intA gene produced thermostable proteases, confirming their virulence nature. The PCR-restriction fragment length polymorphism (PCR-RFLP) of whole fimA gene of serogroup B revealed the predominance of serotype B5 (82.97%) of serogroup B. This information suggests that serotype B5 is the predominant serotype of D. nodosus associated with severe footrot lesions in sheep in Jammu & Kashmir (J&K), India. Hence, this serotype can be a potential vaccine candidate for the effective control and treatment of ovine footrot.
相似文献2. LLM appears to be a good source of protein and calcium.
3. Food intake was not significantly affected (P>0.05) with dietary LLM inclusion up to 200 g/kg.
4. Inclusion of LLM up to 150 g/kg diet did not influence significantly (P>0.05) the performance of broilers in terms of body weight gain and food efficiency. However, inclusion of LLM at 200 g/kg diet had an adverse effect on weight gain and food efficiency, when compared to other dietary treatments. The profitability over food costs was low with the 200 g LLM/kg diet compared to those of other diets.
5. It may be inferred from these experiments that LLM can safely be included in broiler diets up to 150 g/kg.
6. Studies using force‐feeding and restricted feeding techniques indicated that reduced food intake was not responsible for the growth depression in diets containing higher amounts of LLM. 相似文献