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To clarify the differences in light energy utilization and distribution characteristics of flag leaf为明确不同穗型小麦冠层光能利用和

In two growing seasons of wheat (2016-2018), a field trial with Jimai 22 as test mate-rial was conducted in Shijiawangzi Village, Yanzhou City, Shandong Province. Under three nitrogen levels of 150 (N于2016—2018年小麦生长季,在山东省兖州市史家王子村进行田间试验,供试品种为‘济麦22’,在150(N

To explore the optimal hose length of micro-sprinkling hose irrigation in wheat fields, a field trial taking JiMai 22 as test material was carried out in two growing seasons (2015-2016 and 2016-2017). Three lengths of micro-sprinkling hoses with 80-mm width were used, including 60 m (T为了研究麦田用微喷带灌溉的适宜带长,2015—2016和2016—2017两年度以‘济麦22’为材料,设置了带宽80 mm微喷带下带长为60 m (T

A field experiment was conducted to study the effects of long-term tillage practices on photosynthetic characteristics of flag leaf, dry matter accumulation and its allocation, and grain yield, with a wheat cultivar, Jimai 22, in both 2013-2014 and 2014-2015 growing seasons. Four tillage practices, namely rotary tillage (R), plowing (P), strip rotary tillage and subsoiling at an interval of 2 years (SRS), and rotary tillage and subsoiling at an interval of 2 years (RS), were conducted in field for 9 years since 2007. The results showed that the net photosynthetic rate (P以济麦22为供试材料,在大田条件下,9年定位设置旋耕(R)、翻耕(P)、间隔2年深松+条旋耕(SRS)、间隔2年深松+旋耕(RS)4种耕作方式,在2014—2015年和2015—2016年小麦生长季研究不同耕作方式对小麦旗叶光合特性、干物质积累与分配和产量的影响.结果表明: SRS处理小麦旗叶净光合速率(

Field experiments were conducted during 2013-2014 and 2014-2015 winter wheat growing seasons by using Jimai 22 as test material. Five treatments were designed: W于2013—2014和2014—2015年两个小麦生长季进行田间试验,供试品种为‘济麦22’,设置5个处理,分别为W

A two-year field experiment was conducted in 2014-2015 and 2015-2016 wheat growing seasons to study the effects of micro-sprinkling hose length and width on field water condition, and flag leaf chlorophyll fluorescence characteristics in different sampling districts (D2014—2015和2015—2016年小麦生长季,设置微喷带长宽组合处理:带宽65 mm下设置带长60 m (T

With the large-spike wheat cultivar Shannong 23 as test material,a field experiment was conducted by increasing the relative soil moisture content to 70% and 65% at jointing and anthesis stages. Four nitrogen levels,0 (N以大穗型小麦品种‘山农23’为材料,在大田拔节期和开花期土壤相对含水量分别补灌至70%和65%的条件下,设置4个施氮水平0 (N

Field experiments were conducted during 2012-2014 wheat growing seasons. With no irrigation in the whole stage (WO) treatment as control, three supplemental irrigation treatments were designed based on average relative soil moisture contents at 0-140-cm layer, at jointing and anthesis stages (65% for treatment W1 ; 70% for treatment W2; 75% for treatment W3; respectively), to examine effects of supplemental irrigation on nitrogen accumulation and translocation, grain yield, water use efficiency, and soil nitrate nitrogen leaching in wheat field., Soil water consumption amount, the percentage of soil water consumption and water irrigation to total water consumption in W2 were higher, and soil water consumption of W2 in 100-140 cm soil layer was also higher. The nitrogen accumulation before anthesis and after anthesis were presented as W2, W3W1W0, the nitrogen accumulation in vegetative organs at maturity as W3W2WlW0, and the nitrogen translocation from vegetative organs to grain and the nitrogen accumulation in grain at maturity as W2W3W1W0. At maturity, soil NO3(-)-N content in 0-60 cm soil layer was presented. as W0W1W2W3, that in 80-140 cm soil layer was significantly higher in W3 than in the other treatments, and no significant difference was found in 140-200 cm soil layer among all treatments. W treatment obtained the highest grain yield, water use efficiency, nitrogen uptake efficiency and partial productivity of applied nitrogen. As far as grain yield, water use efficiency, nitrogen uptake efficiency and soil NO3(1)-N leaching were concerned, the W2 regime was the optimal irrigation treatment in this experiment.

A field experiment was conducted to study the effects of supplemental irrigation based on soil moisture on the photosynthesis characteristics and enzyme activity of flag leaf using the wheat cultivar Jimai 20. Three irrigation treatments were designed with target soil moisture of 65% (W₆₅), 70% (W₇₀) and 75% (W₇₅) both at jointing and anthesis stages. Zero-irrigation ( CK) was used as the control. The results showed that the net photosynthetic rate (Pn) of flag leaf in treatment W₇₀ was dramatically higher than in other treatments from 14 to 21 days after anthesis, as well as sucrose content and sucrose phosphate synthase (SPS) activity. The dry matter mass per area of W₇₀ was higher than that of W₆₅ and CK, and was not significantly different from that of W₇₅. The single stem mass of W₇₀ was higher than that of the other treatments. The activities of superoxide dismutase (SOD) and catalase (CAT) and the soluble protein concentration in flag leaf of W₇₀ were significantly higher than in other treatments from 14 to 28 days after anthesis. The malondialdehyde (MDA) content of W₇₀ was lower than that of W₆₅ and CK, and was not significantly different from that of W₇₅ from 14 to 21 days after anthesis. Grain yields of W₇₀ were 8941.4 and 9125.4 kg · hm⁻² in the 2012-2013 and 2013-2014 wheat growing seasons, showing no significant difference with those of W₇₅, but obviously higher than those of W₆₅ and CK. And the water use efficiency (WUE) of W₇₀ was the highest. Considering grain yield and WUE, maintaining the relative soil water content at 70% by supplemental irrigation both at jointing and anthesis stages was the best treatment.

With the high-yielding winter wheat cultivar Jimai 22 as test material, a three-year field experiment was conducted to examine the effects of border length for irrigation on flag leaf water potential, photosynthetic characteristics, dry matter accumulation and distribution of wheat. In the 2010-2011 growing season, six treatments were installed, i. e., the field border length was designed as 10 m (L10), 20 m (L20), 40 m (L40), 60 m (L60), 80 m (L80) and 100 m (L100). In the 2011-2012 and 2012-2013 growing seasons, the field border length was designed as 40 m (L40), 60 m (L60), 80 m (L80) and 100 m (L100). The results showed that the average relative soil water content of the 0-200 cm soil layer was presented as L80, L60L100L40L20L10 at anthesis in the 2010-2011 growing season and as L80, L60L100L40 in the 2011-2012 and 2012-2013 growing seasons. At 11 d and 21 d after anthesis, the water potential, net photosynthetic rate and transpiration rate of flag leaf were presented as L80, L100L60L40L20, L10, and as L80L60, L100L40, L20, L10 at 31 d after anthesis. The coefficients of variability both of the dry matter accumulation at anthesis and maturity and of grain yield in different regions of L80 field were lower than those of L100. The average dry matter accumulation, dry matter accumulation after anthesis and the contribution to grain of L80 were dramatically higher than those of L100, L40, L20 and L10. L80 had the highest average grain yield and water use efficiency, being the best treatment for irrigation in our study.

Taking the high-yielding winter wheat variety Jimai 22 as test material, a field experiment was conducted in 2010-2012 to study the effects of irrigation with different length micro-sprinkling hoses on the soil water distribution in winter wheat growth period and the water consumption characteristics and grain yield of winter wheat. Three micro-sprinkling hose lengths were designed, i. e., 40 m (T40), 60 m (T60) and 80 m (T80). Under the micro-sprinkling irrigation at jointing and anthesis stages, the uniformity of the horizontal distribution of irrigation water in soil increased significantly with the decrease of hose length from 80 to 40 m. When irrigated at jointing stage, the water content of 0-200 cm soil layer in each space of wheat rows had no significant difference within the 0-40 m distanced from the border initial in treatments T40 and T60. When measured at the 38-40 m, 58-60 m, and 78-80 m distanced from the border initial in treatment T80 at jointing and anthesis stages, the water content in 0-200 cm soil layer had the same change pattern, i. e., decreased with the increasing distance from micro-sprinkling hose. The water consumption amounts in 40-60 cm soil layer from jointing to anthesis stages and in 20-80 cm soil layer from anthesis to maturing stages were higher in treatment T40 than in treatments T60 and T80. However, the soil water consumption amount, irrigation amount at anthesis stage, total irrigation amount, and total water consumption amount were significantly lower in treatment T40 than in treatments T60 and T80. The grain yield, yield water use efficiency increased with the hose length decreased from 80 to 40 m, but the flow decreased. Therefore, the effective irrigation area per unit time decreased with the same irrigation amounts. Considering the grain yield, water use efficiency, and the flow through micro-sprinkling hose, 40 and 60 m were considered to be the appropriate micro-sprinkling hose lengths under this experimental condition.

In 2010-2011, a field experiment with high-yielding winter wheat cultivar Jimai 22 was conducted to study the effects of supplemental irrigation based on the measurement of moisture content in different soil layers on the water consumption characteristics and grain yield of winter wheat. Four soil layers (0-20 cm, W1; 0-40 cm, W2; 0-60 cm, W3; and 0-140 cm, W4) were designed to make the supplemental irrigation at wintering stage (target soil relative moisture content = 75%), jointing stage (target soil relative moisture content = 70%), and anthesis stage (target soil relative moisture content = 70%), taking no irrigation (W0) during the whole growth season as the control. At the wintering, jointing, and anthesis stages, the required irrigation amount followed the order of W3W2W1. Treatment W4 required smaller irrigation amount at wintering and jointing stages, but significantly higher one at anthesis stage than the other treatments. The proportion of the irrigation amount relative to the total water consumption over the entire growth season followed the sequence of W4, W3W2W1. By contrast, the proportion of soil water consumption relative to the total water consumption followed the trend of W1W2W3W4. With the increase of the test soil depths, the soil water utilization ratio decreased. The water consumption in 80-140 cm and 160-200 cm soil layers was significantly higher in W2 than in W3 and W4. The required total irrigation amount was in the order of W3W4W2W1, the grain yield was in the order of W2, W3, W4W1W0, and the water use efficiency followed the order of W2, W4W0, W1W3. To consider the irrigation amount, grain yield, and water use efficiency comprehensively, treatment W2 under our experimental condition could be the optimal treatment, i. e., the required amount of supplemental irrigation based on the measurement of the moisture content in 0-40 cm soil layer should be feasible for the local winter wheat production.

In the wheat growth seasons of 2009 -2010 and 2010-2011, six border lengths of 10, 20, 40, 60, 80 and 100 m were installed in a wheat field to study the effects of different border lengths for irrigation on the water consumption characteristics and grain yield of wheat. The results showed that with the increasing border length from 10 to 80 m, the irrigation amount and the proportion of irrigation amount to total water consumption amount, the water content in 0-200 cm soil layers and the soil water supply capacity at anthesis stage, as well as the wheat grain yield and water use efficiency increased, while the soil water consumption amount and the water consumption amount of wheat from jointing to anthesis stages as well as the total water consumption amount decreased. At the border length of80 m, the irrigation amount was smaller, and the water content in upper soil layers was lower, as compared with those at the border length of 80 m, which led to the wheat to absorb more water from deeper soil layers, and thus, the total water consumption increased. At the border length of 100 m, the irrigation amount, soil water consumption amount, and total water consumption amount all increased, and, due to the excessive irrigation amount and the uneven distribution of irrigation water when irrigated once, the 1000-grain mass, grain yield, and water use efficiency decreased significantly, which was not conductive to the water-saving and high-yield cultivation.

Taking two wheat (Triticum aestivum L.) cultivars Jimai 20 and Taishan 22 as test objects, this paper studied the effects of different irrigation treatments on the water soluble carbohydrate contents in penult stem internode and sheath and the grain yield. Four irrigation treatments were installed, i. e. , no irrigation (W0), irrigation at overwintering and jointing stages (W1), irrigation at overwintering, jointing and anthesis stages (W2), and irrigation at overwintering, jointing, anthesis and filling stages (W3). In treatment W0, the contents of total soluble sugar and of fructan with the degree of polymerization (DP)or = 4 and = 3 in the penult stem internode and sheath of the two cultivars at early filling stage and the fructose content at later filling stage were the highest, indicating that the accumulation and degradation of water soluble carbohydrate in the penult stem internode and sheath were promoted under no irrigation, which in turn increased the 1000-grain weight. In treatment W1, the contents of fructan with DPor = 4 and DP = 3 in the penult stem internode and sheath of Jimai 20 at early filling stage, the total soluble sugar and fructose contents at middle and later filling stages, and the grain yield were the highest. In treatment W2, Taishan 22 had the highest contents of fructan with DPor = 4 and DP=3 in the penult stem internode and sheath at early filling stage, lower fructose content at higher filling stage than in treatment W1, and the highest grain yield. Comparing with Jimai 20, Taishan 22 had higher contents of total soluble sugar and of fructan with DPor = 4 in the penult stem internode and sheath at early filling stage and higher content of fructose at later filling stage, and lower grain yield in treatments W0 and W1 but higher grain yield in treatments W2 and W3. In this study, treatments W1 and W2 promoted the accumulation and degradation of water soluble carbohydrate in the penult stem internode and sheath of Jimai 20 and Taishan 22, and gained the highest grain yields of the two cultivars, respectively, being most appropriate irrigation treatments for Jimai 20 and Taishan 22, respectively.

Taking high-yielding winter wheat cultivar Jimai 22 as test material, a field experiment was conducted to study the effects of supplemental irrigation based on measuring soil water content on the wheat photosynthetic characteristics and dry matter accumulation and allocation. Six treatments were installed, i. e., W1 (soil relative water content was 65% at jointing stage and was 70% at anthesis), DW1 (soil relative water content was 65% 10 d after jointing and was 70% at anthesis), W2 (soil relative water content was 75% at jointing and was 70% at anthesis), DW2 (soil relative water content was 75% 10 d after jointing and was 70% at anthesis), W3 (soil relative water content was 80% at jointing stage and was 70% at anthesis), and DW3 (soil relative water content was 80% 10 d after jointing and was 70% at anthesis). In treatments W2 and DW2, the flag leaf photosynthetic rate (P(n)) and phi(PS II) at late filling stage were higher than those in treatments W3 and DW3, respectively, the dry matter accumulation amount at anthesis and maturity stage and the allocation of accumulated dry matter at pre-anthesis to grain were significantly higher than those in treatments W1 and DW1, and the water use efficiency (WUE) and irrigation production efficiency (IPE) were significantly higher than those in W3 and DW3. Under the same irrigation levels, the flag leaf P(n), and phi(PS II) at late filling stage were higher in treatments DW2 and DW3 than in W2 and W3, respectively, and the dry matter accumulation amount at anthesis and its allocation to grain were lower whereas the dry matter accumulation amount after anthesis, the grain yield, WUE, and IPE were higher in DW2 and DW3 than in W2 and W3. Under our experimental condition, DW2 could be the optimal irrigation pattern of high-yielding with high WUE.

Taking three wheat cultivars Jimai 20 (strong gluten), Taishan 23 (medium gluten), and Ningmai 9 (weak gluten) as test materials, a field experiment was conducted to examine the effects of shading at different phases of grain-filling on the grain protein components contents and processing quality. Four treatments were installed, i. e., no shading (S0), shading at early grain-filling phase (from 0 day after anthesis (DAA) to 11 DAA; S1), shading at medium grain-filling phase (from 12 DAA to 23 DAA; S2), and shading at late grain-filling phase (from 24 DAA to 35 DAA; S3). No significant differences were observed in the grain albumin+globulin contents of the three cultivars among the four treatments. Shading increased the grain HMW-GS, LMW-GS, gluten, glutenin, and total protein contents of Jimai 20 and Taishan 23 significantly, and the increments were higher in treatment S2 than in other shading treatments. Treatments S2 and S3 increased the grain protein components contents of Ningmai 9 significantly. Comparing with the control, shading decreased the grain yield significantly, but increased the dough development time, dough stability time, and sedimentation volume, especially for treatment S2, which suggested that the wheat grain quality had a close relationship with the light intensity at medium phase of grain-filling. Overall, the regulation effect of shading at grain-filling stage on the wheat grain yield, grain protein components contents, and indices values of grain processing quality for the test cultivars was in the order of Jimai 20Taishan 23Ningmai 9.

A field experiment was conducted to study the effects of sulfur plus resin-coated urea fertilizer on the winter wheat dry matter accumulation and allocation and grain yield. Four treatments were installed, i.e., sulfur plus resin-coated urea (SRCU), resin-coated urea (RCU), sulfur-amended conventional urea (SU), and conventional urea (U). The coated urea fertilizers were applied as basal, and the conventional urea fertilizers were 50% applied as basal and 50% applied as topdressing. There were no significant differences in the plant dry matter accumulation and grain yield between treatments RCU and U. Under the conditions the available S content in 0-20 cm soil layer was 43.2 mg x kg(-1) and the S application rate was 91.4 kg x hm(-2), treatments SRCU and SU had no significant differences in the dry matter accumulation and allocation after anthesis and the grain yield, but the amount of the assimilates after anthesis allocated in grain, the grain-filling rate at mid grain-filling stage, the 1000-grain weight, and the grain yield in the two treatments were significantly higher than those in treatment RCU. When the available S content in 0-20 cm soil layer was 105.1 mg x kg(-1) and the S application rate was 120 kg x hm(-2), the grain yield in treatment SRCU was significantly higher than that in treatment SU, but had no significant difference with that in treatments RCU and U. These results suggested that from the viewpoints of dry matter accumulation and allocation and grain yield, the nitrogen released from SRCU had the same regulation effect as the conventional urea 50% applied as basal and 50% applied as topdressing, while the regulation effect of the sulfur released from SRCU was controlled by the available S content in 0-20 cm soil layer. When the soil available S content was 43.2 mg x kg(-1), the released sulfur could promote the dry matter accumulation after anthesis and the grain-filling, and increase the grain yield significantly; when the soil available S content was 105.1 mg x kg(-1), the released sulfur from SRCU had no significant effect in increasing grain yield. Excessive S-amendment could even induce the decrease of grain yield.

A field experiment was conducted to examine the effects of irrigation amount on the water consumption, flag leaf physiological characteristics, and grain yield of wheat under the nitrogen application rates 180 kg x hm(-2)(N180)) and 240 kg x hm(-2)(N240). Four irrigation regimes were designed, i.e., no irrigation during whole growth period (W0), irrigation with 60 mm water before sowing (W1), irrigation with 60 mm water before sowing and at jointing stage, respectively (W2), and irrigation with 60 mm water before sowing, at jointing stage, and at flowering stage, respectively (W3). In treatment W0, the water consumption amount below 100 cm soil layer was lower than that in other treatments; and in treatments W1 and W2, the water consumption amount in 100-200 cm and 0-200 cm soil layers was higher than that in treatment W3. The soil water consumption amount in 0-80 cm soil layer, the consumption percentage from flowering to maturing stage, and the total water consumption amount were all higher under N240 than under N180. At mid and late grain-filling stages, the relative water content (RWC) and water potential (psi w) of flag leaves were higher in treatments W2 and W3 than in treatments W0 and W1. The RWC and psi w at late grain-filling stage were higher in treatments N240W0 and N240 than in N180W0 and N180 W1, respectively, but had no significant differences between treatments N240W2 and N180W2, and N240W3 and N180W3. In this study, treatment N180W2 had the higher grain yield, water use efficiency (WUE), and nitrogen use efficiency, while over-irrigation increased the water consumption amount, and decreased the WUE, irrigation water use efficiency, and irrigation benefit.

With the high-yielding winter wheat cultivar Jimai 22 as test material, a field experiment was conducted in Yanzhou of Shandong to examine the effects of regulated deficit irrigation on the water consumption and water use efficiency (WUE) of the cultivar. Five treatments were installed, i.e., the soil relative moisture content at sowing, jointing, and anthesis stages being 80%, 65% and 65% (W0), 80%, 70% and 70% (W1), 80%, 80% and 80% (W2), 90%, 80% and 80% (W3), and 90%, 85% and 85% (W4), respectively. Under the condition of 228 mm precipitation in growth season, the total water consumption was higher in treatments W1 and W4 than in treatments W0, W2, and W3, and no difference was observed between treatments W1 and W4. Comparing with W4, treatment W1 decreased the water storage in 0-200 cm soil layer and the water consumption by wheat from jointing to anthesis stages, but increased the water consumption from anthesis to maturity stages. The water consumption rates at the stages from jointing to anthesis and from anthesis to maturity in treatment W4 were higher. Under regulated deficit irrigation, treatment W0 had higher WUE, but the grain yield was the lowest. The WUE in other treatments increased first, and then decreased with increasing irrigation amount. Both the water consumption and the grain yield were the highest in treatments W1 and W4, and treatment W1 had higher irrigation water use efficiency and irrigation benefit than treatment W4, being the best irrigation regime of high-yielding and water-saving in our study.

Field experiments were conducted in Tai' an and Yanzhou of Shandong Province in 2004-2005 and 2005-2006 to study the effects of irrigation stage and amount on the accumulation and translocation of fructan in winter wheat penult stem and sheath after anthesis and the water use efficiency. No irrigation in whole growth period promoted the translocation of fructan from penult stem and sheath to grain at late grain-filling stage. Irrigation with 60 mm water at jointing and anthesis stages increased the flag leaf photosynthetic rate and photo-assimilate accumulation after anthesis, and the contribution of the photo-assimilates to the grain. Irrigation with 60 mm water at jointing, anthesis, and grain-filling stages, and with 90 mm water at jointing and anthesis stages decreased the flag leaf photosynthetic rate at late grain-filling stage, increased the photo-assimilate accumulation before anthesis and the contribution of the photo-assimilates to the grain, and reduced the translocation of the photo-assimilates after anthesis to the grain. Excessive irrigation also increased the contents of fructan with the degree of polymerization (DP)or = 4 and = 3 in penult stem and sheath at late grain-filling stage, limiting the translocation of fructan from penult stem and sheath to grain. Irrigation with 60 mm water at jointing and anthesis stages led to a higher grain yield and the highest water use efficiency, while irrigation with 60 mm water at jointing, anthesis, and grain-filling stages, and with 90 mm water at jointing and anthesis stages had little effects on the grain yield but decreased the water use efficiency.

A field experiment was conducted to study the effects of water-nitrogen interaction on the flag leaf photosynthetic rate, penult stem fructan content, fertilizer N use efficiency, and soil water use efficiency of strong gluten wheat variety 'Jimai 20'. Three N application levels (N0, 0 kg x hm(-2); N1, 180 kg x hm(-2); and N2, 240 kg x hm(-2)) and four irrigation schedules (W0, no irrigation; W1, irrigation before sowing and at jointing and flowering stages; W2, irrigation before sowing, before wintering, and at jointing and flowering stages; W3, irrigation before sowing, before wintering, and at jointing, flowering, and grain-filling stages) were designed. The irrigation amount was 60 mm each time. Among the N treatments, treatment N1 had a higher flag leaf net photosynthetic rate and penult stem fructan content, and the highest grain yield, apparent N use efficiency, agronomic N use efficiency, and water use efficiency. Treatment N2 had a higher penult stem fructan content than treatments N0 and N1. No N application and applying excessive N did not benefit the increase of grain yield, fertilizer N use efficiency, and water use efficiency. Treatment W1 promoted the fructan accumulation in penult stem and accelerated the translocation of the accumulated fructan to grain, being beneficial to the increase of grain yield. Treatment N1W1 had the highest grain yield, and higher fertilizer N use efficiency and water use efficiency. Excessive irrigation and N application increased the flag leaf net photosynthetic rate and penult stem fructan content, but decreased the fertilizer N use efficiency and water use efficiency, with no significant effects on grain yield.

Field experiment was conducted in 2005 -2007 to study the effects of irrigation amount and stage on the water consumption characteristics, grain yield, and water use efficiency of wheat. The results showed that the variation coefficient of the proportion of soil water consumption amount to total water consumption amount was significantly higher than that of precipitation to total water consumption amount, suggesting the relatively wide regulation range of soil water use efficiency. The proportions of irrigation amount, precipitation, and soil water consumption amount to total water consumption amount were 31.0%, 38.9%, and 30.1% in treatment W3 (irrigated at jointing and flowering stages, with total irrigation amount of 120 mm), and 51.7%, 32.4%, and 15.9% in treatment W5 (irrigated before winter and at jointing, flowering and grain-filling stages, with total irrigation amount of 240 mm), respectively, indicating that treatment W3 had a significantly higher proportion of soil water consumption amount to total water consumption amount than treatment W5. Though treatments W2 (irrigated before winter and at jointing stage) and W3 (irrigated at jointing and flowering stages) had the same irrigation amount (120 mm), the water consumption amount during the period from flowering to maturing was significantly higher in W3 than in W2, while the water consumption amount before jointing was significantly lower in W3 than in W2. The water consumption pattern in treatment W3 was in agreement with the water requirement pattern of wheat, which was the physiological basis of high water use efficiency.

With stepwise and one-factor non-linear regression analyses, and based on the meteorological data during the period from anthesis to maturity at 31 experimental sites in Shandong Province, this paper studied the relationships of the kernel quality of 4 strong gluten- and 12 medium gluten wheat cultivars with main meteorological factors in 1999-2003. The results showed that for strong gluten- and medium gluten wheat cultivars, the optimum mean temperature for dough stability time was 20.0 degrees C and 20.5 degrees C, the optimum mean difference of diurnal temperature for protein content was 12.7 degrees C and 11.7 degrees C, the optimum precipitation for sedimentation volume and dough stability time was 48.6 mm and 52.1 mm, and 53.5 mm and 53.9 mm, and the optimum total sunshine for sedimentation volume and dough stability time was 297 h and 299 h, and 295 h and 298 h, respectively. The effects of single meteorological factor on the protein content, sedimentation volume, and dough stability time of wheat cultivars were not identical. Based on the comprehensive evaluation of weather condition, Shandong Province was divided into three production zones for the production of wheat, i.e., central and east Shandong adaptable for strong gluten- and medium gluten- wheat cultivars, northwest and southwest Shandong sub-adaptable for strong gluten- and medium gluten- wheat cultivars, south Shandong sub-adaptable for strong gluten wheat cultivars and adaptable for medium gluten wheat cultivars.

The study with 15N tracing techniques showed that basal application of K did not increase the N and K accumulation in wheat plant when the available K content in 0-20 cm soil layer was 118.5 mg x kg(-1), but increased the accumulation significantly when the soil available K content was 79.0 mg x kg(-1). When the fertilizer K was 1/2 basal-applied and 1/2 top-dressed at elongation stage, the absorbed fertilizer N and soil N by plant as well as the residual N of top-dressed N in soil were increased with increasing K application rate, while the fertilizer N loss decreased. Compared with basal application, the split application of K increased the accumulated amount, uptake efficiency, and productive efficiency of N and K significantly. When the K application rate was 135 kg x hm(-2), split application of K promoted the absorption of top-dressed and soil N by plant, and increased the residual N of top-dressed N in soil. The results also showed that K application increased the grain yield and its protein and wet gluten contents. At the same K application rate, split application had better effect than basal application, and treatment K45 +45 (45 kg x hm(-2) as basal and 45 kg x hm(-2) top-dressed) showed the best effect. Applying excessive K tended to decrease wheat yield and its quality.