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11.
Susan Mary Philip John Fosu-Nyarko Sadia Iqbal Zhaohui Wang Michael G. K. Jones 《Plant pathology》2022,71(3):702-714
Plant hosts can be engineered to disrupt the development of sedentary plant-parasitic nematodes or proper functioning of the feeding sites the nematodes induce. The use of constitutive promoters to express dsRNAs or nematode inhibitor proteins may be unreliable because of possible silencing or yield penalty from continuous expression in a plant host. This ill-effect can be avoided if a root-specific, nematode-responsive promoter (NRP) is used to drive the target nematode-inhibitory message. This study used the In Plant Activation (INPACT) system to express a barstar-controlled barnase in galls of Meloidogyne javanica and assessed how the engineered tobacco lines affected the growth and development of the nematodes. Of the 11 combinations of four NRPs and the CaMV 35S promoter assessed, the AtCel1 and TobRB7 combinations activated specific expression of split β-glucuronidase (GUS) and barnase genes in and around giant cells. The same NRP combination directed expression of the barnase gene in tobacco roots also constitutively expressing the barstar gene (SPBB transgenic lines). On roots of six T1 SPBB lines, there was up to 94% reduction in the number of galls with significantly smaller adult females compared to those on wild-type plants. Some of the females on lines SPBB4-1 and SPBB-4-2, for example, were not associated with galls. The results indicated the engineered plants disrupted M. javanica development and demonstrate the potential for controlled and localized expression of peptides, such as those that could block specific effectors, to disrupt initiation, formation, establishment, or proper functioning of feeding cells induced by damaging sedentary nematodes. 相似文献
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Niamatullah Khan Fazal Yazdan Saleem Ud Din Sadia Gull Sohrab Khan 《Archives of Agronomy and Soil Science》2013,59(5):581-597
Farmers normally practice conventional tillage ((CT), disk plowing, cultivator, rotavator, and leveling) in cotton (Gossypium hirsutum L.) with 15 cm intra-row spacing to avoid risks of poor plant stand and obtain higher yield. However, CT is costly besides it has adverse effects on soil and crop when sown after wheat. Conservation tillage [zero tillage (ZT) or reduced tillage (RT)] with suitable spacing can reduce production cost, increase cotton yield and quality, and it has favorable effects on soil properties. Field experiments were conducted to evaluate cotton response to tillage (ZT, RT, and CT) and intra-row spacing (15.0, 22.5, 30.0, 37.5 cm). Results revealed that RT produced higher bolls plant?1, boll weight, seed cotton yield, ginning out turn, fiber length and strength than ZT and CT. Mean boll weight, seed cotton yield, earliness, and fiber qualities were optimum at 22.5 cm spacing. Tillage × spacing interaction showed optimum boll weight, earliness, and fiber strength with 15.0–22.5 cm spacing under RT. CT with 22.5 cm spacing also performed better in terms of boll weight and fiber strength; however, 15.0 cm spacing resulted in earlier maturity. RT with 22.5 cm spacing is an alternative to CT for higher yield, earliness, and quality of cotton besides environmental safety. 相似文献
13.
ABSTRACTOn-growing of horse mackerel is not known in the world. Recently, we have initiated on-growing of the Mediterranean horse mackerel in the Black Sea. Therefore, we aim to compare proximate composition and fatty acid profile of on-growing and wild horse mackerels to evaluate the effect on their nutritional value. Captured horse mackerels less than 13 cm were kept on-growing in sea cages and fed sea bass feed for a year in the southern Turkish Black Sea. Results showed seasonal variations in the proximate contents and fatty acid profile of both on-growing and wild fish groups (p < 0.05). Protein contents of the wild horse mackerel group were significantly higher than the on-growing mackerel group, while the opposite situation was observed for lipid contents (p < 0.05). Despite higher eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels (as fatty acid methyl esters %) of wild horse mackerel in comparison with on-growing group, much higher EPA + DHA contents were accounted for in on-growing fish in the edible portion resulting from higher lipid contents of these samples. The results suggest that lower amounts of fish meat, 50–90 g, from on-growing mackerel would cover the daily suggested value of EPA + DHA; this level is calculated as 51–150 g for wild fish meat. 相似文献
14.
Physical and mechanical properties of medium density fiberboards (MDF) made from various mixtures of wood fibers and stone pine (Pinus pinea L.) cones were evaluated using European standards. MDF panels were manufactured using standardized procedures that simulated industrial production at the laboratory. Six panel types were made from mixtures of wood fiber/cone flour, 100/0, 90/10, 80/20, 70/30, 60/40, and 50/50 percents, respectively. Addition of the cone flour into the MDF significantly reduced formaldehyde emission from the panel. In addition, the addition of 10% cone flour also improved water resistance of the MDF panels made using urea–formaldehyde (UF) resin. However, further addition of the cone flour into the panel negatively influenced their water resistance. Flexural properties and internal bond strength decreased with the increase of cone flour content in the panel. The UF resin is the main source of formaldehyde emission from the UF-bonded wood-based panels. Depending on addition of the cone flour in the panels, the formaldehyde emission values ranged from 2.6% to 55.3% lower than the panels made from 100% wood fiber. Based on the findings obtained from this study, pine cone can be used as a renewable biological formaldehyde catcher as an alternative to the traditional formaldehyde catchers for E1 Class MDF manufacture. 相似文献
15.
Effect of wood species,digester conditions,and defibrator disc distance on wettability of fiberboard
Wettability of medium density fiberboard (MDF) surface affects paint or adhesive application and is, thus, of importance in the course of furniture manufacturing. This study investigated the effects of wood species, digester conditions and defibrator disc distance on the wettability properties. It was found that the wettability of the MDF significantly decreased with increasing the defibrator disc distance and increased with the increment in the severity of the digestion conditions. The highest wettability was found for samples made of beech wood having an average contact angle value of 74.5°, followed by poplar wood (76.5°), birch wood (79.7°), the mixture (1:1) of scots pine and beech wood (82.9°), and scots pine wood (86.4°), respectively. 相似文献
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Malou Delplancke Mariana Yazbek Nils Arrigo Anahí Espíndola Helene Joly Nadir Alvarez 《Genetic Resources and Crop Evolution》2016,63(2):221-234
The genus Prunus L. is large and economically important. However, phylogenetic relationships within Prunus at low taxonomic level, particularly in the subgenus Amygdalus L. s.l., remain poorly investigated. This paper attempts to document the evolutionary history of Amygdalus s.l. and establishes a temporal framework, by assembling molecular data from conservative and variable molecular markers. The nuclear s6pdh gene in combination with the plastid trnSG spacer are analyzed with bayesian and maximum likelihood methods. Since previous phylogenetic analysis with these markers lacked resolution, we additionally analyzed 13 nuclear SSR loci with the δµ2 distance, followed by an unweighted pair group method using arithmetic averages algorithm. Our phylogenetic analysis with both sequence and SSR loci confirms the split between sections Amygdalus and Persica, comprising almonds and peaches, respectively. This result is in agreement with biogeographic data showing that each of the two sections is naturally distributed on each side of the Central Asian Massif chain. Using coalescent based estimations, divergence times between the two sections strongly varied when considering sequence data only or combined with SSR. The sequence-only based estimate (5 million years ago) was congruent with the Central Asian Massif orogeny and subsequent climate change. Given the low level of differentiation within the two sections using both marker types, the utility of combining microsatellites and data sequences to address phylogenetic relationships at low taxonomic level within Amygdalus is discussed. The recent evolutionary histories of almond and peach are discussed in view of the domestication processes that arose in these two phenotypically-diverging gene pools: almonds and peaches were domesticated from the Amygdalus s.s. and Persica sections, respectively. Such economically important crops may serve as good model to study divergent domestication process in close genetic pool. 相似文献
18.
Muhammad Naveed Saifullah Umair Riaz Ghulam Murtaza Sadia Bibi Ammara Arooj Qamar uz Zaman 《Paddy and Water Environment》2018,16(4):867-873
Sewage contains several trace elements of environmental concern, and cadmium (Cd) is one of the most mobile elements in soil–plant system that can pose drastic effects on plants and human health due to its long persistence and non-biodegradability nature in environment. It is necessary to prevent its entry into food chain for better food quality and human health. Present study was designed to evaluate the effectiveness of different water management practices, viz. W1: flooding throughout the growing season, W2: flooding after 4 days of disappearance of standing water (DAD), W3: flooding till heading and after that flooding of soil after 4 days of DAD, W4: Aerobic condition throughout growing season (flooding after 8 days) for reducing Cd concentration in rice grain grown under varying levels of Cd (0, 20, 40 mg kg?1) spiked soil. Results revealed that grain yield declined with increasing Cd levels but maximum plant height (89.3 cm), straw yield (16.9 g) and grain yield (22.5 g pot?1) was observed where pots were flooded till heading and thereafter flooding. Cadmium concentration increased with increasing concentration of Cd in soil. Further, it is added that the lowest Cd concentration in shoot, grain and husk and translocation factor were observed under W3 when the soil was spiked with 40 mg kg?1. In crux, continuous flooding till heading and thereafter flooding after 4 DAD can significantly decrease the grain Cd concentration without compromise on yield. 相似文献
19.
An experiment was conducted in Nicaragua to determine the effect of feeding different levels of foliage from Moringa oleifera Lam (synonym: Moringa pterygosperma Gaertner) to dairy cows on intake, digestibility, milk production and milk composition. The treatments were: Brachiaria brizantha hay ad libitum, either unsupplemented or supplemented with 2 kg or 3 kg of Moringa on a dry matter (DM) basis. Six Bos indicus cows of the Creole Reyna breed, with a mean body weight of 394 ± 24 kg were used in a replicated 3 × 3 Latin square design. Supplementation with Moringa increased (P < 0.05) DM intake from 8.5 to 10.2 and 11.0 kg DM day− 1 and milk production from 3.1 to 4.9 and 5.1 kg day− 1 for B. brizantha hay only and supplementation with 2 kg and 3 kg DM of Moringa, respectively. Milk fat, total solids and crude protein and organoleptic characteristics, smell, taste and colour, were not significantly different between the diets. Apparent digestibility coefficients of DM, OM, CP, NDF and ADF increased (P < 0.05) in the diets supplemented with Moringa compared with B. brizantha hay alone. The results showed that the inclusion of Moringa as a protein supplement to low quality diets improved DM intake and digestibility of the diet and increased milk production but did not affect milk composition. 相似文献
20.
Pierluigi Bonello Thomas R. Gordon Daniel A. Herms David L. Wood Nadir Erbilgin 《Physiological and Molecular Plant Pathology》2006,68(4-6):95-104
Coniferous trees are often dominant species in both boreal and temperate forests, wherein they play critical roles in ecosystem function. In natural environments, ecosystem stability appears to be the norm, notwithstanding the co-occurrence of insect and microbial species inherently capable of killing their host trees. Adaptive plasticity of host trees involving inducible mechanisms of resistance against invading organisms is likely to play a crucial role in these interactions. We hypothesize that systemic-induced resistance represents a common and important phenomenon in coniferous trees, allowing for a balanced allocation of resources between growth and defense. 相似文献