Role of ‘<Emphasis Type="Italic">Candidatus</Emphasis> Liberibacter solanacearum’ and <Emphasis Type="Italic">Bactericera cockerelli</Emphasis> Haplotypes in Zebra Chip Incidence and Symptom Severity

Two haplotypes of the pathogen, ‘Candidatus Liberibacter solanacearum,’ (Lso) and four haplotypes of the insect vector, Bactericera cockerelli, are associated with zebra chip disease of potato. Whether disease severity or incidence is influenced by pathogen or insect haplotype is poorly understood. The role of Lso ‘A’ and ‘B,’ transmitted by three haplotypes of B. cockerelli, on disease severity and incidence in eight potato cultivars was analyzed. Both haplotypes of Lso induced tuber symptoms. In general, Lso B caused higher incidence of symptoms, and greater reduction in tubers compared with Lso A. Lso B was associated with more severe tuber symptoms, producing fewer mild or moderate tuber symptoms. Lso A was associated with less severe tuber symptoms, despite being able to induce severe symptoms. Disease incidence, tuber yield, and symptom severity ratings were not dependent upon the psyllid haplotype transmitting the pathogen, suggesting that pathogen, not insect haplotype affects Lso transmission.     

Barley (1→3; 1→4)-β-glucan and arabinoxylan content are related to kernel hardness and water uptake

Harder kernels in barley are thought to be a factor affecting the modification of the endosperm during malting by restricting water and enzyme movement within the endosperm. The objective of this study was to investigate the relationship between kernel hardness, water uptake and the endosperm composition in barley. A range of barley samples from 2003 and 2004 crops were analyzed for kernel hardness by the Single Kernel Characterization System, water uptake during steeping and chemical composition of the endosperm including (1→3; 1→4)-β-glucan, arabinoxylan and total protein. Both (1→3; 1→4)-β-glucan and arabinoxylan content of the endosperm were correlated significantly with kernel hardness in barley samples from both 2003 (r=0.873 and 0.601, respectively, p<0.01) and 2004 seasons (r=0.764 and 0.501, respectively, p<0.01). Hardness of the kernel was highly correlated with its water uptake in both 2003 and 2004 samples (r=−0.853 and −0.752, respectively, p<0.01). β-Glucan content of the endosperm was also correlated significantly with the kernel water uptake for both years (2003: r=−0.752, p<0.01; 2004: r=−0.551, p<0.01). Arabinoxylan content of the endosperm was correlated significantly with the kernel water uptake for the 2003 barley but not for 2004 barley (2003: r=−0.523, p<0.01; 2004: r=−0.151, p>0.01). Protein content of the endosperm was not correlated with the kernel hardness in either year. These results demonstrate that endosperm cell wall components may have significant impact on kernel hardness as well as water uptake of barley.     

Determination of the Antimicrobial and Antioxidative Properties and Total Phenolics of Two “Endemic” Lamiaceae Species from Turkey: <Emphasis Type="Italic">Ballota rotundifolia</Emphasis> L. and <Emphasis Type="Italic">Teucrium chamaedrys</Emphasis> C. Koch

This study was designed to examine the in vitro antimicrobial and antioxidant activities and the amount of total phenolics of the methanol extracts of Ballota rotundifolia L. and Teucrium chamaedrys C. Koch. In the case of antimicrobial activity tests, polar sub-fractions of the methanol extracts of plant species exhibited weakest antimicrobial activity when compared with the non-polar ones. While, non-polar sub-fraction of B. rotundifolia showed moderate activity against A. lwoffii, C. perfringens and the yeasts, T. chamaedrys performed excellent activity pattern against all of the tested microorganisms. The sub-fractions were also screened for their possible antioxidant activities by two complementary tests, namely DPPH free radical-scavenging and β-carotene/linoleic acid assays. Non-polar extracts of the plant species remained inactive in both test systems. On the other hand polar extracts showed remarkable antioxidant activities. In DPPH system, free radical scavenging effect of T. chamaedrys was measured as 18.00 ± 1.42 μg.mg⁻¹. It is extremely important to point out that, polar sub-fraction of T. chamaedrys is found as effective as the positive control BHT. Non-polar sub-fraction of T. chamaedrys found to have the highest total phenolic amount (97.12 ± 1.28 μg/mg). Results obtained from this experiment confirm the relationship between the amount of phenolics and biological activities.     

Preparation and characterization of electrospun polyvinyl alcoholstyrylpyridinium/<Emphasis Type="Italic">β</Emphasis>-cyclodextrin composite nanofibers: Release behavior and potential use for wound dressing

Biocompatible polyvinyl alcohol (PVA)-styrylpyridinium (SbQ)/β-cyclodextrin (β-CD) composite nanofibers were obtained by electrospinning in this study. PVA-SbQ was used as the foundation polymer as well as crosslinking agent, β-CD was incorporated to achieve expected properties such as improved mechanical properties and thermal stability. The Fourier transform infrared spectroscopy (FTIR) spectra confirmed the existence of β-CD, and the morphologies and average fiber diameters of the electrospun composite nanofibers were also analyzed by SEM. X-ray diffraction patterns (XRD) of PVA-SbQ/β-CD composite nanofibers revealed that the inclusion of β-CD in the nanofibers affected the ordered phase of PVA. Besides, the thermal analyses revealed the improvement in the thermal properties for PVA-SbQ/β-CD composite nanofibers. It was found that the crosslinked composite nanofibers showed a clear higher tensile strength (TS) as well as a greater elongation at break (EB). Eventually, antifungal drug griseofulvin (GSV) has been loaded into the composite nanofibers by formation of its inclusion complex with β-CD in aqueous solution, ultraviolet light (UV-Vis) spectral analysis showed that the drug-loading nanofibers had certain sustained release effect.     

Floating Photocatalyst Based on Poly(ε-caprolactone) Foam and TiO<Subscript>2</Subscript> Nanoparticles for Removal of Textile Dyes

This study discusses a novel approach for fabrication of floating photocatalyst which can be efficiently exploited for photodegradation of dyes in aqueous solutions. A fabrication of the floating photocatalyst consisted of two steps: transformation of the poly(ε-caprolactone) beads (PCL_b) into poly(ε-caprolactone) foam (PCL_f) with porous structure in supercritical carbon-dioxide and subsequent loading of PCL_f with TiO₂ nanoparticles (NPs). Morphological characterization of the PCL_f before and after TiO₂ NPs loading was carried out by FESEM. The presence of titanium on the surface and inside the PCL_f was detected by EDX. Photocatalytical activity of the floating photocatalyst was investigated in aqueous solution of textile dyes C.I. Acid Orange 7 (AO7) and C.I. Basic Yellow 28 (BY28) which were exposed to lamp that simulates the sun light. In addition to sustainable floatability for a long period of time, developed floating photocatalyst exhibited high rate of photodegradation since the complete discoloration of AO7 and BY28 solutions and photocatalysts alone occurred after 300 and 180 min of illumination, respectively. Its photocatalytic activity was preserved after three repeated photodegradation cycles with unchanged chemical structure that was confirmed by FTIR analysis.     

Are soil‐adjusted vegetation indices better than soil‐unadjusted vegetation indices for above‐ground green biomass estimation in arid and semi‐arid grasslands?

Accurate estimation of grassland biomass has been a central focus due to its importance in ecosystem processes and carbon cycles. This study aimed to examine whether the performance of soil‐adjusted vegetation indices for estimating above‐ground green biomass was better than that of soil‐unadjusted vegetation indices in arid and semi‐arid grasslands. Above‐ground green biomass in desert steppe of Inner Mongolia and corresponding moderate‐resolution imaging spectroradiometer (MODIS) surface reflectance 8‐day composite MOD09Q1 data were collected during late September of 2013. Results showed that soil‐adjusted SAVI (soil‐adjusted vegetation index), MSAVI (modified soil‐adjusted vegetation index), OSAVI (optimized soil‐adjusted vegetation index), TSAVI (transformed soil‐adjusted vegetation index), ATSAVI (adjusted transformed soil‐adjusted vegetation index) and PVI (perpendicular vegetation index) did not improve estimation accuracy over soil‐unadjusted simple ratio (SR) and normalized difference vegetation index (NDVI), due to low green vegetation cover (<30%) in the study area. Our results suggest that these soil‐adjusted vegetation indices may be not suitable for describing green vegetation information in arid and semi‐arid grasslands with low green vegetation cover (<30%).     

Weight loss and morphology changes of electrospun poly(<Emphasis Type="Italic">?</Emphasis>-caprolactone) yarns during <Emphasis Type="Italic">in vitro</Emphasis> degradation

In this study, the in vitro degradation of yarns made from PCL electrospun fibers containing various concentrations of ampicillin sodium salt was investigated. PCL fibers were electrospun and collected as well-aligned fiber bundles and then twisted into yarns. Yarn weight loss, morphology changes in the yarns, and morphology changes in the fiber microstructure with degradation were evaluated. Results showed that the electrospun PCL yarns degraded slowly with a weight loss less than 3 % in 12 weeks. The addition of various concentrations of ampicillin salt increased the degradation rate slightly. The morphological changes observed in fiber microstructure suggested that the degradation underwent bulk erosion and the degradation began with the amorphous regions. Revealed by the fiber morphological changes with degradation, the microstructure of electrospun PCL fibers followed the fringed fibril fiber model. The fiber arrangement in the yarn was impaired by the in vitro degradation environment as well.     

棉花良种补贴，“鸡肋”还是“飨宴”

 实践证明,棉农是国家实施棉花良种补贴的最大受益者，实现了棉花良种补贴的主要目的。有人对棉花良种补贴持有不同的态度，是因为棉农、种子企业和基层农技推广部门等相对独立的利益主体，均以从项目实施中获利多少来评价政策的优劣。棉种市场混乱是制约项目实施的关键因素,要提高项目实施水平，必须采取综合措施，重点是整治棉种市场，简化补贴操作程序。     

In vitro fermentation kinetics and end-products of cereal arabinoxylans and (1,3;1,4)-β-glucans by porcine faeces

Purified and semi-purified polysaccharides characteristic of cereals were fermented in vitro with a pig faecal inoculum, using the cumulative gas production technique, to examine the kinetics and end-products of fermentation after 48 h. It was shown that arabinoxylan and mixed linkage (1,3;1,4) β-glucan were rapidly fermented if soluble, while less soluble substrates (insoluble arabinoxylan, maize and wheat starch granules, and bacterial cellulose) were more slowly fermented. Relevant monosaccharides were fermented at very similar rates to soluble polymeric arabinoxylan and β-glucan, showing that depolymerisation was not a limiting step, in contrast to some previous studies. Bacterial cellulose is shown to be a useful model substrate for fermentation of plant cellulose which is difficult to obtain without harsh chemical treatments. Fermentation end-products were related to kinetics, with slow carbohydrate fermentation resulting in increased protein fermentation. Ratios of short-chain fatty acid products were similar for all arabinoxylan and β-glucan substrates.     

Does pre‐grazing herbage mass really affect herbage intake and milk production of strip‐grazing dairy cows?

The effect of pre‐grazing herbage mass (HM) on herbage intake and milk production of strip‐grazing dairy cows is usually studied at the same herbage allowance (HA). In the literature, the effect of HM seems to be affected by the cutting height above which HA is estimated. The aim of this 2 × 3 factorial study was to determine whether the effect of HM (low vs high HM) on herbage intake, milk production and grazing behaviour of dairy cows is affected by the HA estimation height (ground level vs 2·5 vs 5 cm). Two HMs were compared in three different ways: at same HA above ground level (SHA₀), at same HA above 2·5 cm (SHA₂) and at same HA above 5 cm (SHA₅). During two consecutive years, twenty‐four Holstein‐Friesian dairy cows in mid‐lactation were assigned to one estimation height in an incomplete switchback design, with two 14‐d periods. There was an interaction between HM and estimation height for herbage intake and milk production. The effect of HM on herbage intake was positive, null and negative when HMs were compared at SHA₀, SHA₂ and SHA₅, respectively. This study may have practical implications on future research for studying, directly or indirectly, the effect of pre‐grazing HM under strip‐ or rotational‐grazing management, and on modelling herbage intake at grazing.     

Does post‐grazing sward height influence sward characteristics,seasonal herbage dry‐matter production and herbage quality?

Extending the grazing season through the production and utilization of high‐quality forage is a key objective in grassland‐based dairy production systems. Grazing swards to a low post‐grazing sward height (PGSH) is a strategy for improving grass utilization. A grazing experiment conducted in Ireland investigated immediate and subsequent effects of PGSH on sward production, utilization and structural characteristics. Swards were grazed to 2·7 cm (severe; S1) or 3·5 cm (moderate; M1) from 10 February to 18 April 2010 (Period 1; P1). From 19 April, each P1 paddock was halved and grazed to either 3·8 cm (S2) or 4·8 cm (M2), until 30 October (Period 2; P2). The first grazing rotation was +7 d on S1 swards compared with M1 swards (45 d), due to greater herbage utilization (+0·22). Herbage production during P1 was not affected by PGSH but a severe PGSH during this period reduced subsequent herbage production: 13·9 (S1) vs. 15·5 t dry matter (DM) ha^?1 (M1) by the end of the study. Leaf proportion was increased (+0·10) on S2 swards compared with M2 swards, but M2 swards produced 1·2 t DM ha^?1 more herbage during P2. Despite the relatively lower level of sward utilization obtained from moderate grazing in P1 (3·5 cm) and P2 (4·5–5·0 cm), such levels of PGSH increased DM production while maintaining sward quality, compared with severe grazing (2·7 cm in P1 and 3·5–4·0 cm in P2).     

Distribution and Abundance of Necrophagous Flies (Diptera: Calliphoridae and Sarcophagidae) in Maranh?o,Northeastern Brazil

This study aimed at surveying the local calliphorid and sarcophagid species in Maranhão State (Brazil) to determine their distribution and abundance, as well as the distribution of exotic Chrysomya species. In total, 18,128 calliphorid specimens were collected, distributed in 7 genera and 14 species. The species Hemilucilia semidiaphana (Rondani, 1850) and Paralucilia paraensis (Mello, 1969) were new state records. Chrysomya albiceps (Wiedemann, 1819) and Cochliomyia macellaria (F., 1775) were the most abundant species, and the exotic species of Chrysomya together contributed more than 50% of total blow fly abundance. The abundance distribution of the calliphorid community conformed to a log series model, characterized by a steep curve that reflects an assemblage with a high degree of dominance. For the Sarcophagidae, a total of 14,810 specimens were collected and distributed in 15 genera, 11 subgenera, and 52 species. Tricharaea (Sarcophagula) occidua (F., 1794) and Peckia (Sarcodexia) lambens (Wiedemann, 1830) were the most abundant species. The abundance distribution of the species followed a log normal model, with a gentler slope, consistent with a more uniform community. The cumulative species curve for the sarcophagids did not reach the asymptote. Forty-three sarcophagid species were new state records and 22 were new records for the Brazilian northeast, which emphasizes the need for a continued survey in this region.     

Chemical Composition and Nutritional Value of Unripe Banana Flour (<Emphasis Type="Italic">Musa acuminata</Emphasis>, var. Nanicão)

Banana flour obtained from unripe banana (Musa acuminata, var. Nanicão) under specific drying conditions was evaluated regarding its chemical composition and nutritional value. Results are expressed in dry weight (dw). The unripe banana flour (UBF) presented a high amount of total dietary fiber (DF) (56.24 g/100 g), which consisted of resistant starch (RS) (48.99 g/100 g), fructans (0.05 g/100 g) and DF without RS or fructans (7.2 g/100 g). The contents of available starch (AS) (27.78 g/100 g) and soluble sugars (1.81 g/100 g) were low. The main phytosterols found were campesterol (4.1 mg/100 g), stigmasterol (2.5 mg/100 g) and β-sitosterol (6.2 mg/100 g). The total polyphenol content was 50.65 mg GAE/100 g. Antioxidant activity, by the FRAP and ORAC methods, was moderated, being 358.67 and 261.00 μmol of Trolox equivalent/100 g, respectively. The content of Zn, Ca and Fe and mineral dialyzability were low. The procedure used to obtain UBF resulted in the recovery of undamaged starch granules and in a low-energy product (597 kJ/100 g).     

Anthocyanins of <Emphasis Type="Italic">Pithecellobium dulce</Emphasis> (Roxb.) Benth. Fruit Associated with High Antioxidant and α-Glucosidase Inhibitory Activities

Red arils of Pithecellobium dulce fruit, commonly known as guamuchil, show high antioxidant (AOx) and α-glucosidase inhibitory (IαG) activities, which have been mainly associated with the content of unknown anthocyanins. In this study, the AOx (i.e., DPPH and ABTS as Trolox equivalents, μmol TE/g) and IαG (as half-maximal inhibitory concentration, IC₅₀, mg/mL) activities of the anthocyanin-rich fraction (ARF) obtained from red arils were contrasted with those of the methanol extract (ME), and the main ARF anthocyanins were characterized by HPLC-DAD-ESI-MS, GC-MS and ¹H-NMR. The AOx and IαG values of the ARF (DPPH?=?597.8; ABTS?=?884.01; IαG?=?0.06) were better than those of the ME (DPPH?=?41.5; ABTS?=?142.3; IαG?=?17.5); remarkably, the ARF IαG value was about 42 times lower than that of acarbose. The main anthocyanins in ARF were pelargonidin 3-O-glucoside and cyanidin 3-O-glucoside. Thus, the consumption of red P. dulce arils could provide health benefits for prevention/treatment of chronic degenerative diseases such as diabetes.     

Characterizing Zebra Chip Symptom Severity and Identifying Spectral Signatures Associated with ‘<Emphasis Type="Italic">Candidatus</Emphasis> Liberibacter solanacearum’-Infected Potato Tubers

Zebra chip (ZC) disease has been a threat to the US potato industry for nearly two decades. ZC is associated with the bacteria ‘Candidatus Liberibacter solanacearum’ (Lso), which is transmitted by the potato psyllid, Bactericera cockerelli (?ulc) (Hemiptera: Triozidae). ZC reduces yield and quality, due to discoloration of the tuber tissue. Symptom severity is affected by the time of infection and early-season infections express relatively higher degrees of ZC. Although tubers infected late in the growing season, i.e. within 2 weeks of harvest, express minimal to no symptoms, they may proceed to express ZC symptoms following storage. Currently, visualization of ZC symptoms in tubers is used by processors to estimate the percentage of ZC-affected tubers in truckloads of potatoes. This approach, however, is time consuming and relies on evaluations of a small sample size. Thus, it is likely to fail in detecting the asymptomatic late infections. Using several potato genotypes infected at different times during the growing season, this study was set to determine if visible and near infrared spectrometry, and infrared thermal imaging, can be used to distinguish ZC-affected tubers, and to predict the severity of ZC symptoms. The subjective symptom score categorization, commonly used in ZC studies, corresponded with the percentage of the symptomatic area in the tubers sliced at the solon attachment end. The percentage of symptomatic area was also correlated with Lso titer. Reflectance effectively distinguished infected and uninfected tubers with high accuracy; the combined wavelengths 468, 582, 680 and 720-nm were the most effective in predicting symptom severity. Near infrared (NIR) and infrared (IR) thermal imaging failed to distinguish tubers based on Lso infection status after storage. The quantitative measure of ZC severity, and the effectiveness of some visual wavelengths in detecting ZC may help to facilitate selection assays for ZC resistance. While in our study infrared imaging did not appear to be effective in distinguishing Lso- affected tubers after storage, additional studies with field harvested tubers are still needed to evaluate the effectiveness of VIS, NIR and IR spectrometry in screening for ZC.     

Effects of selected extrusion parameters on physicochemical properties and in vitro starch digestibility and β-glucan extractability of whole grain oats

Whole grain oat flour was extruded under different moisture contents (15%, 18%, 21%), barrel temperatures (100 °C, 130 °C), and screw speeds (160 rpm, 300 rpm, 450 rpm), and selected physicochemical properties, in vitro starch digestibility, and β-glucan extractability of the extrudates were analyzed. An increase in screw speed resulted in an increase in radial expansion index, water absorption index, and water solubility index. Screw speed significantly affected slowly and rapidly digestible starch. Moderate screw speed (300 rpm) led to higher slowly digestible starch with an accompanying decrease in rapidly digestible starch. Low moisture conditions (15%) resulted in the highest resistant starch and water-extractable β-glucan. Under the conditions used in this study, extrusion did not result in changes in water-extractable β-glucan molecular weight. Thus, extrusion might be beneficial in improving functionality and consumer acceptability by affecting physicochemical properties, in vitro starch digestibility, and β-glucan extractability of oat extrudates.     

On-farm evaluation of the ‘push–pull’ technology for the control of stemborers and striga weed on maize in western Kenya

The ‘push–pull’ technology is a novel pest management strategy developed for control of stemborers and striga weed, Striga hermonthica, in maize-based farming systems in eastern Africa, where maize is intercropped with desmodium, a forage legume, and Napier grass is planted as a border crop. Desmodium repels stemborer moths while Napier grass attracts them. Desmodium also suppresses the parasitic striga weed through a series of mechanisms ranging from shading to allelopathy through the root system. The technology is currently being disseminated among smallholder farmers in eastern Africa and adoption rates are rising. Our on-station studies have reported efficacy of this technology against the two pests resulting in increased grain yields. The current study was conducted between 2003 and 2006 in 14 districts in western Kenya to assess effectiveness of the technology under farmers’ own conditions. Twenty farmers from each district, who had adopted the technology, were randomly selected for the study. Each farmer had a set of two plots, a ‘push–pull’ and a maize monocrop. Seasonal data were collected on percentage of maize plants damaged by stemborers, the number of emerged striga, plant height and grain yields. Similarly, farmers’ perceptions on the benefits of the technology were assessed using a structured questionnaire. Stemborer damage and striga counts to maize plants were significantly lower in the ‘push–pull’ plots than in the maize monocrop plots. Similarly, maize plant height and grain yields were significantly higher in the former. Farmers rated the ‘push–pull’ technology significantly superior in having reduced stemborers and striga infestation rates and increased soil fertility and grain yields. These results demonstrate that the technology is equally effective in controlling both pests with concomitant yield increases under farmers’ conditions in the districts studied.     

Does relative time of emergence affect stand composition and yield in a grass–legume mixture? Kura clover (Trifolium ambiguum)–meadow bromegrass (Bromus biebersteinii) and Kura clover–orchardgrass (Dactylis glomerata) mixtures

Establishing Kura clover (Trifolium ambiguum) in mixtures with grass species is challenging, because slow growth of clover seedlings results in low competitive ability. This study examined establishment success by altering time of seeding of the grass component to reduce competition with Kura clover seedlings. Two trials, one of Kura clover–meadow bromegrass (Bromus biebersteinii) and the other Kura clover–orchardgrass (Dactylis glomerata) mixtures were planted in Edmonton, Alberta. Grasses were seeded at the same time as the clover, or introduced when the clover reached one true leaf or three true leaves, in the autumn of the planting year or the following spring. Species composition varied significantly between treatments. When sown at the same time, Kura clover contributed 31 and 14% of yield in the establishment year when sown with meadow bromegrass and orchard grass, respectively. Delaying grass sowing until Kura clover had one or three leaves gave a higher percentage of Kura clover compared with planting at the same time. Autumn and spring grass sowing resulted in stands of 78 and 80% clover with meadow bromegrass, and 74 and 67% clover with orchardgrass. Altering the competitive advantage of the grass species to produce a more balanced mixture was successfully achieved by delaying seeding of the grass relative to Kura clover. A long interval before introducing the grass (autumn or following spring), was not successful as established Kura clover seedlings have an increased competitive ability.     

Effects of partial rootzone drying on yield,yield components,and irrigation water use efficiency of canola (<Emphasis Type="Italic">Brassica</Emphasis>?<Emphasis Type="Italic">napus</Emphasis> L.)

Effect of PRD (partial rootzone drying) on yield and yield components of canola (Brassica napus L.) was investigated in greenhouse conditions. The treatments were: T₁, full watering of both sides of roots; T₂, alternate irrigation on both sides; T₃, half of irrigation water in T₁ was given to one side; T₄, same as T₃ but without plate; T₅, same as T₂ but without plate. In T₁, T₂, and T₃ treatments, the boxes were evenly separated into two compartments with thin plates. The results showed that grain yield of T₁ to T₅ treatments was 18.11, 16.38, 12.44, 9.29, and 8.66 g plant⁻¹. T₂ treatment increased plant height by 46.9% and 1000-seed weight by 17.8%, but reduced lateral branches by 16.7% and number of pods by 24%, over T₁ treatment. T₂ treatment was the most efficient (irrigation water use efficiency = 0.679 kg m⁻³) and treatment T₅ was the least efficient (0.359 kg m⁻³). The difference between irrigation water use efficiency (IWUE) of T₂ and T₅, and T₃ and T₄ treatments, was significant (p < 0.05). Therefore, halving the amount of applied irrigation water and applying this water alternatively on both sides of the root zone will produce the highest IWUE. This study showed that PRD irrigation management has high influence on rooting system of canola. This phenomenon could affect nutrients uptake and consequently all aspects of plant growth and development.     

山东棉花生产“十一五”回顾及“十二五” 发展对策建议

 回顾了“十一五”期间山东棉花生产现状,分析了种植面积稳定、单产提高、总产增加的主要原因。在此基础上,展望了“十二五”期间山东棉花生产面临的形势,提出了稳定发展的对策建议。