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991.
Rice stem borer (Chilo agamemnon Bles.) is a primary insect pest of rice and is a major limiting factor to rice production. Breeding for insect-resistant crop varieties has been an economic way of integrated pest management (IPM) as it offers a viable and ecologically acceptable approach. This study was aimed to evaluate rice genotypes for their resistance against rice stem borer. Seven parental genotypes with twenty one F1 crosses were evaluated for genotypic variation in field experiments. Analysis of variance revealed significant differences for the studied traits in almost all crosses and parents. In addition, the mean squares of parents versus their crosses were signifi- cant for stem borer resistance and other associated traits. Moreover, both general combining ability (GCA) and specific combining ability (SCA) variances were highly significant for all characters studied in the F1 generation. Based on GCA, 4 genotypes (Sakha101, Gz6903-3-4-2-1, Gz9577-4-1-1 and Hassawi) exhibited highly significant negative values for stem borer resistance (–0.53, –1.06, –0.18 and –0.49, respectively) indicating they are the best combiners for stem borer resistance. Based on SCA analysis, nine cross combinations showed highly significant negative effects for stem borer resistance. Similarly, the cross Giza178 Hassawi was the best combination with significantly highest value for early maturity. In addition, seven crosses showed highly significant negative SCA for plant height trait. On the other hand, for panicle length, number of primary branches/panicle, panicle weight and 1000-grain weight, seven, four, eight and six crosses showed highly significant positive SCA, respectively. The result further revealed that the non-additive dominance genetic variance was higher than the additive variance for all evaluated traits indicating that non-additive genetic variances have a role in their inheritance. The broad-sense heritability estimates were high for all the studied traits. The stem borer resistance was significantly correlated with panicle weight and 1000-grain weight, which also showed a highly significant correlation with grain yield/plant. Thus these traits can be effectively employed in a breeding program to confer resistance against stem borer infestation in rice. It was further supported by biplot analysis, which clustered these potentially important traits into two quadrants showing their importance in any future breeding program to control stem borer infestation. This study has contributed valuable information for evaluation of genetic diversity in the local rice germplasm and its utilization in futuristic rice genetic improvement programs.  相似文献   
992.

Understanding the historical context of an area enables an incoming conservationist to reflect on their role in communities and to better position themselves both politically and socially within them. Here, we explore how outside agencies and institutions, including a former colonial power, have affected and influenced local communities who share their landscape with Barbary macaques (Macaca sylvanus) in Bouhachem forest, north Morocco. In the context of initiating Barbary macaque conservation activities, we interviewed representatives from local governmental and nongovernmental organizations, city dwellers, and villagers about the historical, political, and social context of the study site. We found that villages around Bouhachem were politically and socially marginalized and discriminated against by the state and urban society. The existence of these divisions and the outside agencies’ simplistic view of villages as homogeneous communities negatively influenced conservation interventions, because people resisted initiatives imposed on them without prior consultation. We found that Bouhachem villagers have been, and still are, excluded from meaningful participation in the conservation of the forest and this finding encouraged us to decolonize our own practice. We engaged meaningfully with members of the surrounding communities and responded to news of erroneous stories about our activities by developing a project working in three villages that included all households. Based on our experiences, we recommend that all conservationists conduct historical and qualitative research to gain a deeper, more nuanced understanding of the communities they work in. This understanding should encourage conservationists to recognize their own social and cultural biases and to decolonize their practice. Attending to our own position may help us to avoid underestimating and alienating people who view conservation actions through a very different but equally valid lens.

التخلص من التداعيات الاستعمارية في المحافظة على الرئيسيات :دراسة حالة من شمال المغربخلاصة : إن فهم السياق التاريخي لمنطقة معينة، يمكّن المحافظ البيئي الوافد من التفكير في دوره في المجتمعات، ولانسجامٍ سياسيٍ واجتماعي أفضل داخلها. هنا نكتشف كيف أثرت الوكالات والمؤسسات الخارجية ، بما في ذلك القوة الاستعمارية السابقة، على المجتمعات المحلية التي تتعايش مع قرود المكاك البربري (Macaca sylvanus) في غابة بوهاشم شمال المغرب. في سياق بدء أنشطة الحفاظ على المكاك البربري، أجرينا مقابلات مع ممثلين من المنظمات الحكومية وغير الحكومية المحلية وسكان المدن والقرويين حول السياق التاريخي والسياسي والاجتماعي لموقع الدراسة. وجدنا أن القرى المحيطة بغابة بوهاشم كانت مهمشة و معرضة للتمييز ضدها سياسياً واجتماعياً من قبل الدولة والمجتمع الحضري. و أثر بشكل سلبي وجود هذه الانقسامات والنظرة السطحية للوكالات الخارجية للقرى على أنها مجتمعات متجانسة، على تدخلات الحفظ البيئي، لأن الناس رفضوا أي مبادرة مفروضة عليهم دون استشارة مسبقة. و وجدنا أن القرويين في بوهاشم كانوا ولا يزالون مستبعدين من المشاركة الهادفة في الحفاظ على الغابة، وهذا الاكتشاف شجعنا على التخلص من التداعيات الاستعمارية في ممارستنا. لقد تواصلنا بشكل هادف بأعضاء من المجتمعات المحيطة، واستجبنا لأخبار القصص الخاطئة حول أنشطتنا من خلال تطوير مشروع يعمل في ثلاث قرى شمل جميع الأسر. بناءً على تجاربنا، نوصي جميع دعاة الحفاظ على البيئة بإجراء بحث تاريخي ونوعي لاكتساب فهم أعمق وأكثر دقة للمجتمعات التي يعملون فيها. يجب أن يشجع هذا الفهم دعاة الحفاظ على البيئة على التعرف على التحيزات الاجتماعية والثقافية الخاصة بهم، والتخلص من التداعيات الاستعمارية في ممارساتهم.قد يساعدنا الاهتمام بموقفنا الخاص على تجنب الإبعاد و التقليل من شأن الأشخاص، الذين ينظرون إلى إجراءات الحفاظ على البيئة من منظور مختلف تمامًا لكن عادل .

  相似文献   
993.
International Journal of Primatology - Throughout the equatorial tropics, forest conversion to agriculture often fragments crucial primate habitat. In 30 years, 80% of the alluvial lowland...  相似文献   
994.

To develop an effective genome editing tool for blueberry breeding, CRISPR-Cas9 and CRISPR-Cas12a were evaluated for their editing efficiencies of a marker gene, beta-glucuronidase (gusA), which was previously introduced into two blueberry cultivars each a single-copy transgene. Four expression vectors were built, with CRISPR-Cas9 and CRISPR-Cas12a each driven by a 35S promoter or AtUbi promoter. Each vector contained two editing sites in the gusA. These four vectors were respectively transformed into the leaf explants of transgenic gusA blueberry and the resulting transgenic calli were induced under hygromycin selection. GUS staining showed that some small proportions of the hygromycin-resistant calli had non-GUS stained sectors, suggesting some possible occurrences of gusA editing. We sequenced GUS amplicons spanning the two editing sites in three blueberry tissues and found about 5.5% amplicons having editing features from the calli transformed with the 35S-Cas9 vector. Further, we conducted a second round of shoot regeneration from leaf explants derived from the initial Cas9- and Cas12a-containing calli (T0) and analyzed amplicons of the target editing region. Of the newly induced shoots, 15.5% for the 35S-Cas9 and 5.3% for the AtUbi-Cas9 showed non-GUS staining, whereas all of the shoots containing the Cas12a vectors showed blue staining. Sanger sequencing confirmed the editing-induced mutations in two representative non-GUS staining lines. Clearly, the second round of regeneration had enriched editing events and enhanced the production of edited shoots. The results and protocol described will be helpful to facilitating high-precision breeding of blueberries using CRISPR Cas technologies.

  相似文献   
995.
Plant Growth Regulation - Ethylene is an endogenous plant hormone associated with natural senescence and abscission of plant organs. Ethylene release from the degradation of 2-chloroethylphosphonic...  相似文献   
996.
997.

In this study we tested the hypotheses that root classes would exhibit distinctive anatomical and architectural responses to drought stress, and that those responses would vary along the root axes. The root systems of four maize (Zea mays L.) sweet corn genotypes designated SC1, SC2, SC3 and SC4 were phenotyped under well-watered and drought treatments in greenhouse mesocosms, permitting increasing stratification of moisture availability as the drought progressed. Anatomical and architectural responses to drought were evaluated for each root class. Lignin distribution was assessed by image processing of UV-illuminated root cross-sections acquired by laser ablation tomography. The two cultivars with less biomass reduction under drought, SC3 and SC4, substantially enhanced lateral root development along the apical segments of axial roots when plants were grown with drought stress. These segments grew into the deeper part of the mesocosm where more moisture was available. Apical segments of the axial and large lateral roots from drought-stressed plants were thicker and had greater theoretical axial water conductance than basal segments, especially in SC3 and SC4. Basal segments of crown roots of SC3 and SC4 showed increased lignification of the stele under drought. Root anatomical and architectural responses to drought are complex and vary among cultivars and root classes, and along root axes. Drought-induced proliferation of lateral roots on apical segments of axial roots would be expected to enhance deep water acquisition, while lignification of axial roots could help preserve axial water transport.

  相似文献   
998.
Background

Testicular injury is one of the most serious problems associated with diabetes mellitus. The present study aimed to compare the effects of two different doses of nobiletin and analyze its mechanisms of action against diabetes-induced testicular impairment in rats.

Methods and results

Streptozotocin injection was used to induce diabetes. Diabetic rats received nobiletin orally at 10 or 25 mg/kg daily for 30 days. Diabetic rats displayed significant elevations in glucose, glycosylated hemoglobin (HbA1c), Homeostatic Model of Insulin Resistance (HOMA-IR), and pro-inflammatory cytokines, while the serum levels of insulin, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were significantly reduced. Histological changes to positivity for caspase-3 and decreased androgen receptors (AR) immunoexpression were observed in diabetic rats. Both doses of nobiletin improved hyperglycemia, reduced pro-inflammatory cytokines, and augmented insulin, testosterone, LH, and FSH levels. LH and FSH receptors and cytochrome P450 17 α-hydroxylase (CYP17A1) were markedly downregulated in terms of both gene and protein expression in testicular tissues of the diabetic group, effects that were markedly ameliorated with both doses of nobiletin. In addition, both doses significantly reduced lipid peroxidation and caspase-3 immunoexpression and improved the activity of the antioxidant enzymes and AR in testicular tissues of the diabetic group.

Conclusion

Both nobiletin doses showed protective effects against diabetes-induced testicular injury by reducing oxidative stress, hyperglycemia, inflammation, and caspase-3 and upregulating the hypophysis–gonadal axis and AR. The high dose of nobiletin was more effective than the lower one.

  相似文献   
999.
Molecular Biology Reports - The SHANK3 gene encodes a master synaptic scaffolding protein at the excitatory synapse’s postsynaptic density, which is predominantly responsible for constructing...  相似文献   
1000.
Neurochemical Research - Lipoic acid (α-LA) (1,2-dithiolane3-pentanoic acid (C8H14O2S2) is also called thioctic acid with an oxidized (disulfide, LA) and a reduced (di-thiol: dihydro-lipoic...  相似文献   
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