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71.
陈亦辉 《长江蔬菜》2013,(18):41-47
简述了荸荠生产中种质资源收集、分类、对比、抗性鉴定;繁殖、育苗、水肥管理、脱毒技术;轮作、间套模式;主要病虫害及管理措施。介绍了当前荸荠采收、去皮等前处理新技术及设备,传统产品加工以及近年来荸荠皮的功能物质研究、综合利用的一些新进展.并对今后产业发展提出了期望。  相似文献   
72.
In Argentina, peanut production is concentrated in areas where unpredictable and intermittent periods of water deficit occur almost every year especially, during the pod growth period. Florman INTA is the most popular variety among peanut producers, but it is highly sensitive to drought. Manfredi 393 INTA was released as a drought-tolerant variety. Differences between these varieties in radiation interception and crop mass accumulation relative to light levels, as well as in allocation of assimilate to economic yield under water deficit, have not been previously studied.

An experiment was set with two different regimes of water supply. Half of the crop was irrigated (IRR) from sowing to maturity, while the other half received no water between 47 and 113 days after sowing. The fraction of PAR intercepted, (f), leaf area, pod and vegetative above-ground biomass and leaf carbon dioxide exchange rate (CER) were measured periodically during the water deficit period. The leaf area index, degree of leaf folding, canopy extinction coefficient, radiation use efficiency (RUE), partitioning factor, (p), and harvest index (HI) were calculated from the measurements.

Under water stress, f was reduced in both varieties with respect to their controls, and the reduction was proportionally higher in Florman INTA as a consequence of a higher leaf area reduction and degree of leaf folding. However, f remained higher in Florman INTA than in Manfredi 393 INTA due to the enhanced capacity of the former to generate leaf area under non-limiting water supply.

RUE values were higher in Manfredi 393 INTA than in Florman INTA, both under irrigation as well as under severe water deficit, where they were obtained using a two-parameter exponential model. The reason for the higher RUE values in Manfredi 393 INTA was its ability to maintain a higher leaf CER.

Partitioning to pods under irrigation was greater in Manfredi 393 INTA than in Florman INTA, as a result of a longer pod filling period and higher p. Towards the end of podfill, there was a rapid increase of p in Florman INTA, but too late to improve its HI. Under water stress, the time course of p for both varieties was lower than in the IRR treatments and consequently, HI at harvest was reduced. Low HI values could be attributed to some extent to the mechanical impedance of the upper soil layer, caused by water deficit. Mechanical impedance alters the relation among p and HI values obtained under irrigation and water stress. However, even if it is accounted for, cultivars with high HI under IRR conditions usually have high HI under water deficit.  相似文献   

73.
不同采收期对红富士苹果贮藏品质的影响   总被引:19,自引:0,他引:19  
研究了不同采收期对红富士苹果贮藏品质的影响。分别于盛花期后168 d、171 d、174 d、177 d、181 d和183 d采果,冷藏中定期测定几种指标的变化。结果表明,采收期不影响呼吸峰出现的时间,但影响峰值高低;早采的果实失水严重;晚采的果实硬度下降快且腐烂率高;适期采收的果实可溶性固形物、有机酸及vC含量变化幅度小,失水及腐烂少。用于长期贮藏的洛川红富士最佳采收期在盛花期后171~177 d,采收时硬度≥8.4 kg/cm2,可溶性固形物含量≥13.8%。  相似文献   
74.
Evaluation of seed yield, morphological variability and nutritional quality of 27 germplasm lines of Chenopodium quinoa and 2 lines of C. berlandieri subsp. nuttalliae was carried out in subtropical North Indian conditions over a 2-year period. Seed yield ranged from 0.32 to 9.83 t/ha, higher yields being shown by four Chilean, two US, one Argentinian and one Bolivian line. Two lines of C. berlandieri subsp. nuttalliae exhibited high values for most of the morphological traits but were low yielding. Seed protein among various lines ranged from 12.55 to 21.02% with an average of 16.22 ± 0.47%. Seed carotenoid was in the range of 1.69–5.52 mg/kg, while leaf carotenoid was much higher and ranged from 230.23 to 669.57 mg/kg. Genetic gain as percent of mean was highest for dry weight/plant, followed by seed yield and inflorescence length. All morphological traits except days to flowering, days to maturity and inflorescence length exhibited significant positive association with seed yield. The association of leaf carotenoid with total chlorophyll and seed carotenoid was positive and highly significant. The path analysis revealed that 1000 seed weight had highest positive direct relationship with seed yield (1.057), followed by total chlorophyll (0.559) and branches/plant (0.520). Traits showing high negative direct effect on seed yield were leaf carotenoid (−0.749), seed size (−0.678) and days to flowering (−0.377). Total chlorophyll exerted strongest direct positive effect (0.722) on harvest index, followed by seed yield (0.505) and seed protein (0.245).  相似文献   
75.
随着审定制度的改变,大量玉米新品种涌现市场,为了选择适宜豫北区域生产的玉米新品种,指导当地玉米生产,本研究以‘郑单958’作为对照,对30个新审定的玉米品种在本区域大田条件下种植的适应性、抗逆性和宜机收性进行比较。结果表明:参试品种生育期为114~120天,在豫北地区能正常成熟,雌雄花期能够正常相遇,抗逆性较好;产量为8726.97~11973.68 kg/hm2,较对照增产明显的有‘豫单1851’、‘德合187’、‘玉农76’、‘中博510’、‘浚单1538’和‘漯玉16’,增产率分别为10.4%、8.9%、7.5%、7.3%、5.8%、4.5%,其中‘豫单1851’、‘德合187’、‘玉农76’、‘中博510’、‘浚单1538’五个品种收获时水分相对较低,分别为:21.5%、21.7%、19.1%、19.6%、18.2%。研究表明,30个参试品种中‘浚单1538’等5个品种在豫北区域具备机械化籽粒收获性状。  相似文献   
76.
玉米机械化子粒收获是中国玉米未来的发展方向。为了探讨不同玉米自交系材料的配合力及其组配杂交组合的机械化粒收质量影响程度,本研究以7个美国自交系材料作母本,‘新01A3’的5个改良系作父本,采用不完全双列杂交,以组配成的35个玉米杂交组合为试验材料,机械化子粒收获后,测定产量和子粒含水率,计算杂质率、破碎率和田间损失率,并对产量进行配合力分析。结果表明,‘XL2’产量的一般配合力(GCA)最高。5个父本自交系中,‘新A389’产量的一般配合力最高,其次为‘新69’。‘XL6×新69’的产量特殊配合力(SCA)最高,其次为‘XL7×新3764’。对各项性状指标进行相关性分析,结果显示,子粒含水率与破碎率之间存在显著正相关。35个杂交组合中,32个玉米杂交组合的产量与邻近对照相比增幅超过5%,且所有杂交组合的子粒含水率均低于28.0%,均适宜机械化子粒收获。今后应加强对高配合力自交系‘XL2’、‘XL5’和‘新A389’、‘新69’的利用。  相似文献   
77.
Higher harvest index, widely reported as a main trait supporting major improvements in rice yield potential, also supports the higher performance of hybrids over inbreds. Although higher sink size is generally claimed for being the driver of higher grain filling in hybrid rice, it is relevant to question whether efficient sink regulation, that is timing and magnitude of the successive sink activities over crop growth from early stage, plays a role in supporting higher harvest index and is a key feature ensuring higher performance of hybrid rice. The partitioning coefficient (PC), as the increase in dry matter of one single organ over that of shoot, was calculated over short and successive periods to quantify the dynamics of dry matter partitioning. Four hybrid and four inbred genotypes of similar crop duration were grown under the same cropping management on the IRRI farm during a wet and a dry seasons. While PC to blade and sheath was similar for both plant types in both seasons at the early stage, PC to culm of hybrids was higher than that of inbreds, and PC to blade was lower, in the late vegetative and early reproductive phases. During the late reproductive phase, PC to panicle of hybrids was higher than that of inbreds, and PC to culm was lower whereas culm elongation was similar for both plant types. During grain filling, PC to culm was significantly more negative with hybrids which indicated stronger remobilization with hybrids. Specific culm length before anthesis, as low as 40 cm g−1, accounted for storage ability, and at maturity, as high as 130 cm g−1, for remobilization ability. Sink strength index, as a better indicator of dry matter partitioning efficiency than harvest index, and unfilled grain size, as an indicator of assimilate wastage, were suggested as key indices to account for the better sink regulation in hybrid rice and to improve screening protocols for increasing yield potential and tolerance to lodging.  相似文献   
78.
采用裂区设计进行试验,研究刈割处理和收获时间对菊苣根中菊粉产量的影响。结果表明:适度的刈割使菊苣根中菊粉产量显著增加,刈割2次的最大产量为144.4±11.8 g/m2,比不刈割的91.5±9.81g/m2提高了57.8%。过度刈割又使其下降,刈割3次的最大产量为104.4±7.86 g/m2,比刈割2次的144.4±11.8 g/m2降低了38.3%。刈割作用下菊苣根中菊粉产量与收获时间呈显著二次曲线关系。  相似文献   
79.
Quantifying the local crop response to irrigation is important for establishing adequate irrigation management strategies. This study evaluated the effect of irrigation applied with subsurface drip irrigation on field corn (Zea mays L.) evapotranspiration (ETc), yield, water use efficiencies (WUE = yield/ETc, and IWUE = yield/irrigation), and dry matter production in the semiarid climate of west central Nebraska. Eight treatments were imposed with irrigation amounts ranging from 53 to 356 mm in 2005 and from 22 to 226 mm in 2006. A soil water balance approach (based on FAO-56) was used to estimate daily soil water and ETc. Treatments resulted in seasonal ETc of 580–663 mm and 466–656 mm in 2005 and 2006, respectively. Yields among treatments differed by as much as 22% in 2005 and 52% in 2006. In both seasons, irrigation significantly affected yields, which increased with irrigation up to a point where irrigation became excessive. Distinct relationships were obtained each season. Yields increased linearly with seasonal ETc (R2 = 0.89) and ETc/ETp (R2 = 0.87) (ETp = ETc with no water stress). The yield response factor (ky), which indicates the relative reduction in yield to relative reduction in ETc, averaged 1.58 over the two seasons. WUE increased non-linearly with seasonal ETc and with yield. WUE was more sensitive to irrigation during the drier 2006 season, compared with 2005. Both seasons, IWUE decreased sharply with irrigation. Irrigation significantly affected dry matter production and partitioning into the different plant components (grain, cob, and stover). On average, the grain accounted for the majority of the above-ground plant dry mass (≈59%), followed by the stover (≈33%) and the cob (≈8%). The dry mass of the plant and that of each plant component tended to increase with seasonal ETc. The good relationships obtained in the study between crop performance indicators and seasonal ETc demonstrate that accurate estimates of ETc on a daily and seasonal basis can be valuable for making tactical in-season irrigation management decisions and for strategic irrigation planning and management.  相似文献   
80.
收获时间对老芒麦种子产量的影响   总被引:15,自引:2,他引:13  
以生长2年和生长3年老芒麦为试验材料,研究收获时间对其种子产量的影响。结果表明,随着老芒麦种子的成熟,收获的种子产量逐渐增加,在盛花期后26-27d收获可以获得较高的种子产量,延迟收获种子产量则呈下降趋势。生长3年老芒麦同生长2年老芒麦相比,其种子产量下降50%左右。  相似文献   
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