 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Water Deficit on Growth and Yield of Cotton Cultivar Sri Sumrong 60) ผู้เขียน: นางสาวแอนนา สายมณีรัตน์ , ดร.อภิพรรณ พุกภักดี, ศาสตราจารย์ ,  Yves Crozat, ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThe objectives of this study were to determine the effects of water deficit on growth yield and yield components of cotton (Gossypium hirsutum L.). The study has been conducted in the dry season of 1996 (January – July, 1996) at National Corn and Sorghum Research Center, Pak Chong, Nakhon Ratchasima. The experimental design was Randomized Complete Block with 4 replications. The cultivar Sri Sumrong 60 was used in this experiment. Treatments composed of full irrigation applied weekly (T1), stress period at the beginning of square producing stage (T2) and stress period at the early blooming stage (T3). Midday leaf water potential (?1) was used as an indicator for water deficit, when ?1 reached about-2.5 MPa, the irrigation was resumed again. The results revealed that plant height, number of nodes per plant and height to node ratio of T2 and T3 were statistically lower than of T1 during stress period. The production of reproductive organs of T2 and T3 was significantly reduced. Ten days after reirrigation, the recovery and rapid growth occurred in T2 and T3. Thus, total seed cotton yield of T2 and T3 was not significantly different from T1. However, T3 gave the greatest seed cotton yield, approximately 3 ton ha-1. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Response of Cotton Leaf Photosynthesis to Differential Growth Light Environment ) ผู้เขียน:ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์, Yves Crozat, ดร.ศรปราชญ์ ธไนศวรรยางกูร, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractLight is one of the most important resources for plant. Light level in canopy varies greatly. Previous research using individual leaf shading showed no photosynthetic response to reduce light environment to main stem leaves. Our objective was to determine photosynthetic response of main stem, sympodial, and monopodial leaves to differential growth light environment. We monitored light environment on leaf surface and measured photosynthesis rates at different leaf ages. As leaf aged, light environment of main stem leaves slightly decrease while for sympodial and monopodial leaves it rapidly decreased. Pmax for main stem and sympodial leaves rapidly decreased with increasing leaf age. That significant decline in Pmax(70%) of main stem leaves was associated with not-significant reduction in leaf light environment indicated physiological response caused by leaf aging. Finally, the positive correlation between Pmax and differential light environment suggest photosynthetic adaptation of cotton leaves to growth light environment, in addition to physiological changes with leaf aging. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Cotton Leaf Photosynthesis and Age Relationship is Influenced by Leaf Position) ผู้เขียน:ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์, Yves Crozat, ดร.ดวงรัตน์ ศตคุณ สื่อสิ่งพิมพ์:pdf AbstractPhotosynthesis rate per unit leaf area and leaf longevity are significant components of field cotton performance. The objective of this study was to determine the relationship between photosynthesis rate and age for leaves located at different positions in canopy. Cotton cultivars ‘Sri Sumrong 60’ was sowed weekly from June to September 1995 and on May 30, 1996 at Kasetsart University’s Suwan experiment station. Net photosynthesis rates at light saturation (Pmax) were measured using open system portable photosynthesis system equipped with LED lamp. The relationship between Pmax and main stem leaf age, without regard to nodal position, was influenced by plant age. Furthermore, relationships between Pmax and leaf age appeared to be similar for main stem leaves on nodes 3-10. For leaves on nodes 12-15, Pmax declined at slower rate than for nodes 3-15. The main difference of Pmax-age relationships of sympodial and monopodial from main stem leaves seemed to be the proportion of leaves that had Pmax less than the average for main stem leaf at the same leaf age. At specific leaf age, Pmax tended to decline with increase sympodial position. In addition, Pmax of monopodial leaves had very large variation, and were less responsive to leaf age than for main stem leaves. Analysis of Pmax-node position for specific age revealed that for main stem leaves at lower node Pmax peaked earlier and longevity was shorter than leaves at higher modes. Differences in Pmax-age relationships for leaves at various main stem, sympodia, and monopodial position were thought to result from leaf acclimation to limiting available PPF resources. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : The Development and Survival of Fruit in Relation with Plant Structure of Field-grown Cotton) ผู้เขียน:Yves Crozat, Vincent Judais, นางสาวแอนนา สายมณีรัตน์, ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractFruiting pattern and fruit survival of Thai cotton cultivar SSR 60 were investigated during a rainy season trial and two dry-season trials. During the dry-season one trial was managed with the aim of achieving limited plant growth. Plant structure, fruit production and survival were mapped at 2-days intervals. Initiation of first square was delayed by poor plant growth but time between first square and first flower together with boll period of first fruit were mainly temperature dependent. A comprehensive description of fruit phenology and change in plant structure was achieved by plotting the vertical progression of square-appearance, flowering and boll opening of each fruiting position according to time. In each trial, linear models fitted well to the data. Fruits located on P1 fruiting sites displayed a better survival than fruits located on other sites. Despite this difference frequency distribution of shedding with fruit age highlighted the existence of two similar critical stages whatever fruit position considered. The description of fruiting pattern proposed, combined with a monitoring of fruit survival should help understanding differences in fruit number and production in agronomic treatment and farmers’ fields. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Plant Monitoring Techniques for Analyzing Yield Differentiation between Cotton Fields and Improving Crop Management) ผู้เขียน:Yves Crozat, ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractPlant structure components related to variation in yield between 25 cotton fields were investigated in the cotton growing area of Chaibadan District, Lop Buri Province during 1994 and 1995. Survival of Pl fruits (first bud appeared on a sympodium) of the first-ten fruiting nodes together with the changes in Height to Node Radio (HNR) were relevant criteria for analyzing yield differentiation. In a second step their relevance was survival of P1 fruits, together with the changes in node number and height of the main stem provided a meaningful appraisal of the origin and the cause of yield differentiation. From this type of monitoring, standards were generated with the aim of improving crop management through a better adjustment of inputs to actual plant structure. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Mepiquate Chloride on Growth, Fruiting and Yielding Performances of Field-Grown Cotton) ผู้เขียน:Yves Crozat, ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThe effects of Mepiquat chloride (Pix) on the performances of 58 cotton plots were studied during 1994 and 1995 at Chaibadan district, Lop Buri Province. Pix application at early blooming reduced significantly vegetative growth (node production, inter-node length) during the reproductive period and shortened the crop duration. Over all plots the average seed-cotton yield was not improved by Pix despite significant changes in boll distribution pattern and boll-size. Large variation in yield response existed between plots. The response depended on the rate of increase in internode length prior to Pix application together with fruit retention of the first fruiting branches. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Diagnosis on Thai Agrarian Systems for Research Prioritization to Improve the Sustainability and Competitiveness of Cotton Production) ผู้เขียน:Jean-Christophe Castella, Guy Trebuil, Yves Crozat สื่อสิ่งพิมพ์:pdf AbstractSince 1980, cotton production in Thailand has been decreasing steadily while the demand for cotton lint from the national textile industry jumped dramatically. Attempts made to raise again cultivated areas and yields were not able to alter significantly this declining trend. To understand the factors and conditions determining such an unfavorable evolution, diagnostic studies on cotton production systems were carried out by the Development-Oriented Research on Agrarian Systems (DORAS) project at the complementary field, farm and regional scales. Interdisciplinary teams implemented regional historical analyses and zonations, farming systems characterization and classification, as well as cropping systems surveys and experiments at two contrasted sites: the Maenam Kwae Noi valley in Kanchanaburi province and Chaibadan district of Lop Buri province. While insect pests were found to be the most important cause of cotton production declining sustainability and competitiveness at both sites, the findings suggest that the suitable ways to improve the current situation will differ at these two locations. While in the old cotton producing belt of Chaibadan, significant progress can still be achieved through technical improvements in pest, crop and labor management, in Kanchanaburi border area the social status of the migrating Mon cotton growers, very dependent on entrepreneurial village middlemen, makes organizational and social innovations a prerequisite to significant technical advances. An integrated set of agronomic research priorities dealing with cotton plant improvement for pest tolerance and high cottonseed and lint quality, integrated pest management and other decision support tools for better crop monitoring and management came out of these diagnostic analyses and were subsequently used to structure the following phase of DORAS project activities. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Plant Spacing on Growth and Yield of Cotton Cultivar Sri Sumrong 60 Growth in Dry Season) ผู้เขียน:นางสาวแอนนา สายมณีรัตน์, ดร.อภิพรรณ พุกภักดี, ศาสตราจารย์, Yves Crozat, ดร.พูนพิภพ เกษมทรัพย์, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThe objective of this experiment was to study the effects of narrow spacing on growth and yield of cotton cultivar Sri Sumrong 60. Trial was conducted at National Corn and Sorghum Research Center, Pak Chong, Nakhon Ratchasima from January to July 1996. The design of the experiment was a split plot design with 3 replications. Main-Plot treatments consisted of two between row spacing, 1.0 and 0.5 m and the sub-plots were two within row spacing of 0.1 and 0.2 m. Resolts revealed that no spacing effect was found on yield and yield components of cotton. However, the row spacing of 1.0 m had trend to give approximately 10% higher seed cotton yield than of 0.5 m. And within row spacing of 0.1 m also had trend to give 13.5% higher seed cotton yield than of 0.2 m. It is dued to higher value of the efficiency of light conversion of cotton grown in within row spacing of 0.1 m. |