Seed set,size, and development after 4x × 2x and 4x × 4x crosses in citrus     

Asim Esen  Robert K. Soost  Giuseppe Geraci 《Euphytica》1978,27(1):283-294

Summary As triploids produce seedless fruits the best production is investigated. Comparative studies of embryogenesis, seed set, size, and germination were carried out following 4x×2x and 4x×4x crosses. On the average, both crosses yielded similar numbers and proportions of fully developed seeds per fruit. Seed development and germination took place precociously in 4x×2x seeds as compared to 4x×4x ones. The size of 4x×2x seeds was about 1/6 to 1/3 the size of 4x×4x seeds; thus, they were distinguishable from one another on the basis of size. Similarly, it was found that 3x and 4x seeds could be identified based on size following 4x×2x+4x crosses. It was concluded that 4x×2x crosses would be more successful than 2x×4x crosses for producing triploids.  相似文献   

Distribution of essential oils in leaf tissue of an F2 population of Citrus     

Rainer W. Scora  Asim Esen  Junji Kumamoto 《Euphytica》1976,25(1):201-209

Summary The identification and distribution of 17 mono- and sesquiterpenes in an F₂ population produced from selfing of an interspecific F₁ hybrid is presented. A mode of inheritance for most of these components is attempted, percentages of leaf oil components and a correlation matrix are given.  相似文献   

Indole acetic acid and ACC deaminase-producing <Emphasis Type="BoldItalic">Rhizobium leguminosarum</Emphasis> bv. <Emphasis Type="BoldItalic">trifolii</Emphasis> SN10 promote rice growth,and in the process undergo colonization and chemotaxis     

Rumpa Biswas Bhattacharjee  Philippe Jourand  Clémence Chaintreuil  Bernard Dreyfus  Aqbal Singh  Satya Narayan Mukhopadhyay 《Biology and Fertility of Soils》2012,48(2):173-182

This study focuses on the chemotaxis, colonization and rice growth promoting ability of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase-producing rhizobacteria Rhizobium leguminosarum bv. trifolii SN10, previously isolated from root nodules of Trifolium alexandrium L. We show here that R. leguminosarum bv. trifolii SN10 promote the growth of four different rice varieties grown in India in terms of biomass, root branching and N content. In addition, using scanning electron microscopy and viable cell counts, we provide evidence that the bacteria successfully colonize the root surface of the rice variety which showed maximum growth promotion upon inoculation. Not only this, R. leguminosarum bv. trifolii SN10 exhibit a strong chemotaxis response towards the rice seed and root exudates despite the presence of a bacteriostatic phenolic compound, 7-hydroxycoumarin (umbelliferone). Further, R. leguminosarum bv. trifolii SN10 secretion of phytohormones such as IAA and ACC deaminase suggest the potential of the plant growth promoting rhizobacteria to be used as biofertilizer to enhance rice crop production in the subcontinent.  相似文献   

Preservation of Disease-free Shoot Tips of Potato Germplasm through in vitro System     

M K Biswas　M Hossain　R Islam 《中国马铃薯》2005,19(6):321-325

In vegetatively propagated crops,once system ati-cally infected w ith a viral disease,the pathogen canpassed from one generation to the next[1].Especially inpotato,contam ination by a pathogen can severely re-duce the total yield of the crop[2].Traditionally,potatovarieties have been and still m aintained in a fieldgene bank.M aintenance of potato germ plasm in thefield is a m ajor consum er of tim e,m anpower andspace aside from diseases and environm ental stresses.The m ajor disadvantage of …  相似文献   

Dietary protein level, microbial phytase, citric acid and their interactions on bone mineralization of Labeo rohita (Hamilton) juveniles     

Kartik Baruah  Asim K Pal  Narottam P Sahu  Kamal K Jain  Subhas C Mukherjee  & Dipesh Debnath 《Aquaculture Research》2005,36(8):803-812

A feeding trial was conducted for 60 days to study the effect of dietary protein, microbial phytase and citric acid on intestinal digesta pH, bone ash and bone mineral contents in Labeo rohita juveniles. Eight experimental diets were prepared in 2 × 2 × 2 factorial arrangement with crude protein levels (25% and 35%), microbial phytase (0 and 500 U kg^?1), and citric acid (0 and 3%). The 25% crude protein level feed was supplemented with phytase (U kg^?1) and citric acid (%) at the level of 0,0 (C₂₅); 500,0 (T₁); 0,3 (T₂); 500,3 (T₃), and 35% crude protein level feed at 0.0 (C₃₅); 500,0 (T₄); 0,3 (T₅) and 500,3(T₆) respectively. One hundred and twenty juveniles of L. rohita (av. wt. 12.61–13.72 g) were distributed randomly in eight treatments, each of with three replicates. Addition of citric acid in the 25% crude protein feed significantly decreased (P<0.001) feed pH with concurrent decrease in intestinal digesta pH (P<0.001) and increased the bone ash content (P<0.05) by 4.6%. An interaction between citric acid and phytase (P<0.05) was also observed for bone ash content. Increasing the dietary protein content from 25% to 35% significantly decreased (P<0.01) bone Zn content by 14.9%, which was more prominent with the addition of citric acid, resulting in significant interaction between protein and citric acid (P<0.05), but the bone Cu content was significantly increased (P<0.01) with increasing dietary protein content. Dietary supplementation of microbial phytase (500 U kg^?1) significantly increased (P<0.05) bone Na, Ca, K, P and Fe contents by 15%, 12.1%, 17.4%, 9.2% and 40.7%, respectively, whereas bone P and Mn content was significantly increased (P<0.05) by addition of citric acid (3%). Addition of phytase to plant‐based diets increased the bioavailability of minerals, thereby increasing bone mineralization. The effect of phytase was increased because of addition of citric acid (3%).  相似文献   

Metabolic and digestive enzyme activity of Pangasianodon hypophthalmus (Sauvage, 1878) fingerlings in response to alternate feeding of different protein levels in the diet          下载免费PDF全文

Nagung Camder Tok  Kamal Kant Jain  Dhanasekaran L Prabu  Narottam P Sahu  Sukham Munilkumar  Asim K Pal  Gunnur M Siddiah  Pankaj Kumar 《Aquaculture Research》2017,48(6):2895-2911

A feeding trial was conducted for 90 days to assess the metabolic and digestive enzyme activity in response to alternate or mixed feeding of different protein levels in the diet of Pangasianodon hypophthalmus fingerlings. One hundred and forty four fingerlings with an average weight of 5.0–5.5 g were distributed into four experimental groups each with triplicate. Four iso‐caloric diets with varying level of crude protein viz., 35%, 30%, 25% and 20% were made and designated as diet 35P, 30P, 25P and 20P respectively. Four treatments were maintained based on four different feeding schedules such as continuous feeding of diet 35P (35P/35P), alternate feeding of 1 day diet 35P next day diet 30P (35P/30P), alternate feeding of 1 day diet 35P next day diet 25P (35P/25P) and alternate feeding of 1 day diet 35P next day diet 20P (35P/20P). As a result, specific growth rate (SGR) and weight gain percentage were relatively higher in treatment (35P/25P) followed by (35P/35P) and (35P/30P). The metabolic enzymes such as lactate dehydrogenase (LDH), malate dehydrogenase (MDH), glucose‐6‐phosphate dehydrogenase (G6PDH), Glucose‐6‐phosphatase (G6Pase), alkaline phosphatase (ALP), acid phosphatase (ACP), alanine aminotransferase (ALT), aspartate aminotransferase (AST) were expressed better in (35P/35P) group followed by (35P/25P) and (35P/30P) groups. The digestive enzymes, protease and lipase activities were higher in (35P/35P) and (35P/25P) groups. The present study revealed that the better nutrient utilization and growth of 35P/25P group is because of their balanced digestive and metabolic enzyme activities through alternate level of higher and lower protein diet.  相似文献   

Fish meal replacement by soy protein from soymilk in the diets of red sea bream (Pagrus major)          下载免费PDF全文

A. Biswas  H. Araki  T. Sakata  T. Nakamori  K. Kato  K. Takii 《Aquaculture Nutrition》2017,23(6):1379-1389

Six isoenergetic diets were formulated as follows: fish meal (FM) 700 g kg^–1 (control, C), FM 300 g kg^–1 + soy protein concentrate 300 g kg^–1 (SPC), FM 300 g kg^–1 + enzyme‐treated SPC 300 g kg^–1 (ESC), FM 170 g kg^–1 + soy protein isolate 300 g kg^–1 (SPI), FM 160 g kg^–1 + enzyme‐treated SPI 300 g kg^–1 (ESI) and FM 150 g kg^–1 + conglycinin 300 g kg^–1(CG). Forty fish (3.9 g) were randomly distributed into each of eighteen 300‐L tanks, fed twice daily until satiation for 8 weeks. The final body weight, specific growth rate and condition factor did not show significant differences among the fish fed with diets C, SPC, ESC and ESI (p > .05). The survival was significantly lower in fish fed with diets SPI and CG. Feed efficiency was significantly higher in fish fed with diets SPC and C than in fish fed with other diets (p < .05). There were no significant differences in nutrients retention efficiencies in fish fed with diets C, SPC, ESC and ESI. A significantly higher phosphorus retention efficiency in fish fed with soymilk protein diets resulted in lower phosphorus discharge to the environment (p < .05). These results suggest that the soymilk proteins can comfortably replace 570–770 g FM kg^–1 diet of red sea bream juvenile, which will ensure significant ecological benefits through reducing phosphorus load to the environment.  相似文献   

Indicators of soil quality and crop productivity assessment at a long-term experiment site in the lower Indo-Gangetic plains     

Partha Sarathi Ghorai  Sunanda Biswas  Tapan Jyoti Purakayastha  Nayan Ahmed  Tapas Kumar Das  Radha Prasanna  Bharat Hanamant Gawade  Kallol Bhattacharyya  Kanchan Sinha  Priya Singh  Sujit Das 《Soil Use and Management》2023,39(1):503-520

Deterioration of soil quality under resource-intensive modern agriculture in the face of global climate change poses a huge risk to food security. Because of the complex nature, estimators of soil quality often rely upon a limited set of soil attributes, along with statistical data reduction techniques, for developing quality indices, whilst overlooking biological aspects and regional climatic variability. This study screened the most suitable soil quality indexing approaches for a rice-oilseed-based cropping system in the lower Indo-Gangetic plains (IGP). For this, surface soil samples (0–15 cm) were collected from an ongoing long-term fertilizer experiment with a rice-mustard-sesame cropping system in the IGP. The following treatments were assessed for their effect on soil quality: T₁-control, T₂-NPK (recommended NPK doses), T₃-NPKG (NPK + in situ green manuring), T₄-NPKGB (NPK + in situ green manuring + biofertilizer) and T₅-NPKF (NPK + farm yard manure FYM). We found that total organic carbon (TOC), β-glucosidase, CaCl₂ extractable S, alkaline KMnO₄ oxidizable N, activity of urease, amidase enzyme and mean weight diameter (MWD) were sensitive key indicators of soil quality. The NPKF treatment maintained the highest soil quality status (0.80–0.91), both under productivity and environmental protection goals, owing to the availability of decomposable carbon. Regression analysis showed a better agreement of equivalent rice yield with expert opinion (EO; R² = 0.89) than principal component analysis (PCA; R² = 0.76). Finally, we found that the expert opinion approach with the nonlinear scoring function was the best tool for soil quality assessment of the region.  相似文献