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1.
SULFUR APPLICATION EFFECTS ON SOIL PROPERTIES IN A CALCAREOUS SOIL AND ON SUGARCANE GROWTH AND YIELD
Bob Wiedenfeld 《Journal of plant nutrition》2013,36(7):1003-1013
High pH soils limit availability of pH sensitive nutrients including phosphorus (P), even though abundant levels are present. Application of such nutrients to the soil is ineffective because they quickly get tied up in unavailable forms. Elemental sulfur (S) application in a narrow band to lower root zone pH and increase nutrient availability to the crop is a possible economically feasible solution. A four year field study was conducted in which S was applied to sugarcane (Saccharum spp.) at rates up to 1120 kg S ha?1 each of the 1st three years in a band using different application methods. Sulfur application effects on soil pH were gradual, causing only a slight reduction in the application zone after one year; but was long lasting, resulting in continuing substantial declines in soil pH in an adjacent zone four years after the first S application. Soil available P, sulfate (SO4)-S, and salinity levels increased with increasing S applied. Sugarcane plant growth, as indicated by leaf area index during the grand growth period responded to moderate S application levels. Sugarcane yields increased linearly in the plant crop, but showed quadratic responses to S applications in the 1st through 3rd ratoon crops. Initial soil available P levels prior to the first treatment application were at the critical level considered adequate for crop requirements, yet growth and yield increases in response to S application suggest that the critical available soil P levels for sugarcane may be higher than previously established. Sulfur application at rates beyond those necessary to produce maximum yields resulted in salinity problems which probably reduced yields. The ‘stool splitter’ application method, which slices the plant stool using a coulter and places the fertilizer directly in the middle of the furrow caused crop damage and stand loss which persisted for the remainder of the sugarcane crops. Based on the results of this study, a single application of elemental S at up to 1120 kg S ha?1 directly below the seed cane at planting is recommend for sugarcane on a calcareous soil, with no additional applications in later crops. 相似文献
2.
《Communications in Soil Science and Plant Analysis》2012,43(20):2941-2951
Soybean is an important crop for the Brazilian economy, and soil acidity is one of the main yield-limiting factors in Brazilian Oxisols. A field experiment was conducted during three consecutive years with the objective to determine soybean response to liming grown on Oxisols. Liming rates used were 0, 3, 6, 12, and 18 Mg ha?1. Liming significantly increased grain yield in a quadratic trend. Ninety percent maximum economic grain yield (2900 kg ha?1) was achieved with the application of about 6 Mg lime ha?1. Shoot dry weight, number of pods per plant, and 100-grain weight were also increased significantly in a quadratic fashion with increasing liming rate from 0 to 18 Mg ha?1. These growth and yield components had a significant positive association with grain yield. Maximum contribution in increasing grain yield was of number of pods per plant followed by grain harvest index and shoot dry weight. Uptake of nitrogen (N) was greatest and phosphorus (P) was least among macronutrients in soybean plant. Nutrient-use efficiency (kg grain per kg nutrient accumulation in grain) was maximum for magnesium (Mg) and lowest for N among macronutrients. Application of 3 Mg lime ha?1 neutralized all aluminum ions in soil solution. Optimal acidity indices for 90% of maximum yield were pH 6.0, calcium (Ca) 1.6 cmolc kg?1, Mg 0.9 cmolc kg?1, base saturation 51%, cation exchange capacity (CEC) 4.8 cmolc kg?1, Ca/Mg ratio 1.9, Ca?/?potassium (K) ratio 5.6, and Mg/K ratio 3.0. 相似文献
3.
《Journal of plant nutrition》2013,36(10):2243-2259
ABSTRACT Compost significantly enhanced strawberry (Fragaria × ananassa Duch.) plant growth and fruit quality when used as a soil supplement. Adding half strength of Peter nutrient solution (50% fertilizer) to a mixture of 50% soil plus 50% compost was very effective in significantly increasing plant dry weight to approximately double that of controls (without compost), fruit yield by more than 70%, and fruit size by 15% compared to controls in the two strawberry cultivars (“Allstar” and “Honeoye”). Compost and fertilizer also significantly enhanced leaf chlorophyll content. Nitrate reductase activity significantly increased in leaves and roots with the greatest increases when using 50% soil plus 50% compost. Strawberry plants grown with compost had significantly higher levels of nitrogen (N) and potassium (K), but lower levels of manganese (Mn), iron (Fe), molybdenum (Mo), and nickel (Ni) in fruit of both “Allstar” and “Honeoye”. Adding compost to the soil mix did not change zinc (Zn) and cadmium (Cd) levels. Use of compost also significantly increased levels of organic acids (malic and citric acid), sugars (fructose, glucose, and total sugars), soluble solids content, and titratable acidity content in both cultivars. The results indicate that the use of compost can reduce the amount of fertilizer required for optimum strawberry plant growth. 相似文献
4.
Jingzhen Cui Duanwei Zhu Shuijiao Liao Guanglong Liu Liying Ren Wenbing Zhou 《Journal of plant nutrition》2013,36(13):1923-1936
Rape (Brassica napus L.) seedling pot experiments were performed with a red soil treated with goethite which had boron (B) either adsorbed (ad-B-goethite) or occluded (oc-B-goethite). Soil acidity, different forms of manganese in the soils and different elements content of the rape seedlings were determined. It was found that the addition of boron-containing goethite to the soils resulted in increased rape growth, elevated soil pH and decreased exchangeable acidity. Compared with the control, boron-containing goethite elevated the content of exchangeable manganese (Mn) (EXC-Mn), organic matter bound Mn (OM-Mn), reducible oxide Mn (RO-Mn) and residual Mn (RES-Mn) which were difficult to use for plant. Low labile organic matter was significantly correlated with easily reducible oxide Mn (ERO-Mn) (P < 0.01) and RO-Mn (P < 0.05). Middle organic matter and soil pH was significantly (P < 0.05) correlated with RES-Mn. Stepwise regression was used to select the combination of variables that best estimates shoot and root dry weight of rape seedling. Among them, soil pH, EXC-Mn, OM-Mn, RO-Mn and RES-Mn significantly influenced the dry weight of rape seedlings. The addition of boron-containing goethite improved the uptake of iron (Fe), calcium (Ca), magnesium (Mg), and copper (Cu) element and decreased the uptake of Mn and zinc (Zn) element in rape seedling. The results suggested that boron-containing goethite could provide a better soil acidity environment for plant growth; it was also an important agent increasing a part of manganese difficult to use for plant and reducing the activity of soil manganese, which was beneficial to altering rape seedling growth. 相似文献
5.
6.
Shiveshwar Pratap Singh Room Singh Mukesh Prasad Singh Vijay Prasad Singh 《Journal of plant nutrition》2014,37(4):618-632
A field experiment was conducted at farmer's field in Mollisols of Tarai soils in Uttarakhand (India), to assess the direct and residual effect of sulfur fertilization in wheat-soybean cropping sequence. Four levels of sulfur (S; 0, 15, 30, and 45 kg ha?1) were applied to main crop (wheat) along with recommended dose of nitrogen (N), phosphorous (P), and potassium (K). The direct and residual effect of sulfur at highest level showed 27 and 6 percent increase in grain yield of wheat and soybean over control, respectively. The increase in grain yield of wheat was significant at each sulfur level. The direct as well as residual effect of sulfur showed significant increase in sulfur concentration and its uptake by grain and straw except increase in sulfur concentration and uptake by soybean straw. In wheat-soybean cropping sequence, the agronomic efficiency and apparent sulfur recovery decreased with increase in levels of sulfur, but the percent response increased with increasing sulfur application. Different forms of sulfur such as total sulfur, organic sulfur, calcium chloride extractable sulfur, potassium dihydrogen phosphate extractable sulfur, and non-sulfate sulfur in post-harvest soil increased according to sulfur level applied but it decreased under control and also after residual crops. The buildup of sulfur in surface soils was greater than in the deeper soils. Application of sulfur showed the positive sulfur balance and it increased with increase in sulfur level, while it was negative under control. A major portion (46–62%) of applied sulfur contributed to increase in sulfur content of root zone soil followed by unaccounted component (25–40%) and small portion (11–18%) was absorbed by wheat plant as uptake. 相似文献
7.
A hydroponics study was carried out to evaluate the effect of three plant growth promoting rhizobacteria (PGPR) namely, Bacillus mucilaginosus, Azotobacter chroococcum, and Rhizobium spp. on their ability to mobilize potassium from waste mica using maize and wheat as the test crops under a phytotron growth chamber. Results revealed that PGPR significantly improved the assimilation of potassium by both maize and wheat, where waste mica was the sole source of potassium. This was translated into higher biomass accumulation, potassium content and uptake by plants as well as chlorophyll and crude protein content in plant tissue. Among the rhizobacteria, Bacillus mucilaginosus resulted in significantly higher mobilization of potassium than Azotobacter chroococcum and Rhizobium inoculation. Overall, inoculation of maize and wheat plants with these bacteria could be used to mobilize potassium from waste mica, which in turn could be used as a source of potassium for plant growth. 相似文献
8.
J. O. Siqueira W. F. Rocha Jr. E. Oliveira A. Colozzi-Filho 《Biology and Fertility of Soils》1990,10(1):65-71
Summary We studied the effects of limining on growth and nutrient concentrations of Brachiaria decumbens inoculated with five vesicular-arbuscular mycorrhizal (VAM) fungal assemblages which orginated from soils with different acidity. Liming increased plant growth when applied at rates up to 3 g kg-1 soil and depressed growth at higher rates. Mycorrhizal plants grew better than non-mycorrhizal ones in unlimed soil and also liming rates of 4.5 and 6.0 g kg-1 soil. The growth amelioration effects of VAM in highly acid or over-limed soils were related to nutrient uptake. VAM fungi isolated from an acidic soil exhibited a high symbiotic effectiveness and were better adapted to unlimed soil than those that originated from non-acidic soils. VAM root colonization, 90 days after planting, was little affected by liming. Fungal spore production and species compositions were highly affected by liming. A mixture of Glomus diaphanum and Glomus occultum predominated in unlimed soils inoculated with VAM assemblages isolated from non-acidic soils. In these fungal assemblages, an increased liming rate favored Glomus etunicatum over the other VAM fungi. Gigaspora margarita sporulated abundantly when introduced into unlimed soils, but rarely in limed soils. VAM appear to be crucial for the establishment of brachiaria pastures in the nutrient-deficient acidic soils of Central Brazil. It is suggested that liming may cause striking shifts in VAM populations which may, in turn, have a long-term impact on agricultural productivity in the tropics. 相似文献
9.
R. J. A. Cristancho M. M. Hanafi S. R. Syed Omar M. Y. Rafii 《Journal of plant nutrition》2014,37(6):811-827
Exchangeable and soluble soil aluminum (Al) is limiting plant growth in many soils worldwide. This study evaluated the effects of increasing rates of dolomite and magnesium carbonate (MgCO3) on Al3+, pH, dissolved organic carbon, cations, anions, and Al speciation on oil palm Deli dura × AVROS pisifera root growth. Dolomite and MgCO3 additions significantly raised linearly soil solution pH, magnesium (Mg2+), nitrate (NO3 ?) and chlorine (Cl?) concentrations; exponentially decreased the activity of phytotoxic Al species [aluminum (Al3+), aluminum sulfate (Al2SO4), and aluminum fluoride (AlF3)]; and reduced manganese (Mn) concentration and activity. High activity of those species exponentially reduced root dry weight. Optimum oil palm growth was achieved at: <50 μM monomeric Al, < 30 μM Mn, and <0.20 unit of the ratio Al+Mn to calcium (Ca)+Mg. High activity of Al species and Mn in acidic soil solution cause significant reduction of the root growth. Soil acidity alleviation either with dolomite or MgCO3 mitigates the toxic effect of Al and Mn. 相似文献
10.
《Communications in Soil Science and Plant Analysis》2012,43(7):1057-1066
Abstract Results of field trials with sunflowers grown on an Ultisol over three seasons indicated that applications of lime and gypsum had little effect on the boron concentration in plant tissues. Only when 30 kg borax/ha/annum had been applied did soil amelioration slightly but significantly decrease the B concentration in 1‐month‐old sunflower seedlings. Liming for three seasons significantly decreased the B concentration in the topmost mature leaf at flowering only when 30 kg borax/ha/annum had been applied and the pH (N KCl) was 4.4 and above. A pot experiment with the same soil was designed to test whether high pH levels affected B uptake. The reduction of toxic aluminum markedly increased top and root growth but higher rates of line had no further benefit. Liming significantly decreased the B concentration in seedling tope but the total B content of the tops was increased by liming. It appeared that liming to pH (N KCl) 7.0 did not adversely affect the uptake and translocation of B by sunflower roots, and that the decreased B concentration in seedling tops resulted from a dilution effect due to the benefit from liming. 相似文献
11.
The effect of increasing nitrogen fertilizer rates on the development of root nodules, on the symbiotic N2 assimilation, and on growth and yield of broad beans (Vicia faba L.) In pot experiments with broad beans (Vicia faba minor) the effect of increasing N fertilizer rates (0–800 mg N/pot) on nodulation, symbiotic N assimilation, plant growth, and yield has been studied. The plants were harvested at the beginning and at the end of flowering and at maturity. The following results were obtained: 1. No significant yield differences between treatments were found at the 1st and 2nd harvest, with exception of the 800 mg N/pot treatment which gave higher root yields at the first harvest. 2. At the 1st harvest (beginning of flowering) root nodule yield of the N-zero treatment was higher than the root nodule yield of the N treated plants. At later stages, however, no major differences in root nodule yield between the treatments N100 and N200 and the N-zero treatment were obtained. 3. Highest grain yields were obtained in the treatment with the lowest N-rate (100 mg N/pot) and in the treatment with the highest N rate (800 mg N/pot). The absolute highest amount of symbiotically fixed N was produced in the low N treatment (100 mg N/pot). Provided that the soil is low in available N a low fertilizer rate is required in order to exploit the full N2 assimilation potential. 4. The total soil N remained fairly constant throughout the growing period. 相似文献
12.
施磷量对不同磷效率小麦氮、磷、钾积累与分配的影响 总被引：6，自引：0，他引：6
在土培盆栽条件下,以磷高效小麦(CD1158-7、省A3宜03-4)和磷低效小麦(渝02321)为材料,研究了不施磷、施磷(P)10、20和30mg/kg对小麦不同生育时期生物量、籽粒产量及氮、磷、钾的积累与分配的影响。结果表明:(1)随施磷量的减少,不同磷效率品种小麦籽粒产量和生物量均减少;同一施磷处理,磷高效品种籽粒产量和生物产量高于磷低效基因型。不施磷、施磷10mg/kg,高效品种CD1158-7、省A3宜03-4的籽粒产量为低效品种渝02321 的1.84 倍和1.74倍、1.64倍和1.27倍。(2)低磷处理,磷高效品种小麦植株能够积累较多的氮素;扬花期之前,磷高效品种氮素积累量占小麦全生育期积累量的比例高于低效品种。拔节期、孕穗期氮素分配比例为叶>茎>根,扬花期为叶>茎>穗>根,而成熟期为籽粒、颖壳>茎>叶>根。拔节期和孕穗期磷高效品种根的氮素分配比例高于低效品种,而扬花期和成熟期磷高效品种穗(籽粒)氮素分配比例较高。(3)小麦植株磷素积累量主要集中在拔节期以后的生育时期,占全生育期的82.32%~94.23%。低磷处理,高效品种在拔节期和孕穗期磷素积累量高于低效品种,孕穗期尤为突出。扬花期之前,不施磷处理下,磷高效品种根的磷素分配比例较高。(4)不同施磷处理下,拔节期、孕穗期及扬花期,磷高效品种小麦的钾积累量高于低效品种。不同器官钾素分配比例拔节期和孕穗期均为叶>茎>根,扬花期为茎>叶>穗>根,成熟期为茎>叶>籽粒、颖壳>根。磷高效品种在颖壳和籽粒的钾素分配比例高于低效品种。 相似文献
13.
《Communications in Soil Science and Plant Analysis》2012,43(9):1017-1027
Abstract A study to investigate the effect of lime on dry matter yield of maize (Zea mays) and beans (Phaseolus vulgaris) and nodulation of beans grown in three tropical acid soils (two humic Nitosols and one humic Andosol) was carried out in a greenhouse. The soils ranged from 4.2 to 5.0 in pH; 1.74 to 4.56 in %C; 21.0 to 32.0 meq/100g in CEC; 5.10 to 8.10 meq/100g in exchange acidity; 0.60 to 3.20 meq/100g in exchangeable (exch.) Al and 0.13 to 0.67 meq/ 100g in exch. Mn. Exchange acidity and exch. Al decreased with increasing levels of lime in the three soils. Exchangeable Al was reduced to virtually zero at pH 5.5 even in the soils which had appreciable initial amounts. Exchangeable Mn also decreased with increasing levels of lime in the two Nitolsos. Exceptional results, however, were obtained with the Andosol where exch. Mn increased ten‐fold with the first level of lime and then decreased with subsequent levels. In all the soils, mean dry matter yield of beans and maize, and mean nodule dry weight of beans generally increased significantly with increasing lime levels up to pH value of 6.0. The dry matter yield of beans and maize, and nodule weight of beans, however, decreased progressively with increasing lime levels beyond pH 6.0 value. pH range of 5.5 to 6.0 was considered optimum for the growth of maize and beans, and nodulation of beans in these soils. 相似文献
14.
M. R. Pahlavan-Rad S. A. R. Movahedi-Naeini Mohammad Pessarakli 《Journal of plant nutrition》2013,36(6):874-888
The effects of irrigation water rates and seed bed shapes on changes in soil water and salinity status, bulk density, root growth and dry matter (DM) weights of wheat plants (Triticum aestivum L.) were investigated with a split plot design in a field trial in Zahak Agricultural Research Station in Sistan, Iran in 2005. Irrigation intervals after 80 and 160 mm evaporation from class A evaporation pan were used as main plot. Flat surface, single, triple, and six-row beds with a 20 cm row space were used as subplots. Each treatment was replicated four times. Volumetric soil water content and soil electrical conductivity (EC) were measured using Time Domain Reflectometry (TDR) at 0 —20, 20 —40 and 40 —60 cm depths at nine different times during the growing season. Soil water contents were also measured at 0 —10 and 10 —20 cm depths using standard sampling rings at four different times. The three and six-row beds increased the EC of the saturated paste extract with the more frequent irrigation intervals in this coarse textured soil. Soil water content, DM, and root density were always greater with the more frequent irrigations (shorter irrigation intervals). Root density was greatest in 0 —20 cm depth with the single row bed treatment. Grain yield and root density were greatest with single row bed treatment due to the bed shape at the root development stage (possibly due to a reduced mechanical resistance). A greater soil water content by the short irrigation interval increased grain yield and root density via reducing mechanical resistance. With the loamy sand, bulk density and mechanical resistance increased rapidly after cultivation. Bed shape at root development stage might have enhanced root growth and the crop yields. Apparently, mechanical resistance was the most limiting factor with these loamy sand soils than salinity. 相似文献
15.
The aim of this study was to determine the potential of the endophytic actinomycetes that produce plant growth promoters used as co-inoculants with Bradyrhizobium japonicum to promote the growth of soybean. These endophytes exhibited the potential to enhance plant growth, nitrogenase activity of root nodules and plant nutrient uptake. Co-inoculum of B. japonicum with Nocardia alba conferred the maximum yield of root and shoot dry weight. All single-inoculated actinomycetes strains had the ability to enhance plant growth. Noc. alba and Nonomuraea rubra increased total plant dry weight up to 2.14-fold and 2.11-fold, respectively, when compared to the uninoculated controls. Co-inoculations of B. japonicum with each of Noc. alba, Non. Rubra, and Actinomadura glauciflava increased acetylene reduction activity up to 1.7 to 2.7-fold. For plant mineral composition, all of co-inoculation treatments significantly increased the nutrient levels of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) within a soybean plant. 相似文献
16.
通过盆栽和大田试验研究了水和磷互作对旱作水稻生物量和产量的影响。研究表明:土壤含水量和施磷量对旱作水稻生物量和产量有极显著的影响,且二者的交互作用十分明显,影响程度以籽粒> 茎>根。上壤含水量为饱和持水量的60%时对旱作水稻生物量和产量影响较大,而80%和100%时几乎没有影响。旱作水稻生物量和产量均随施磷量的增加而增加。这说明控制土壤水分为饱和持水量的80%时就能完全满足旱作水稻的生长,但要求获得较高的产量时必须注意磷肥的投入,或者采取一些凋控措施提高土壤磷的利用率。 相似文献
17.
The relationship between root age and root physiology is poorly understood, despite its importance for nutrient absorption. In peaches, roots are white when they first appear and then become brown with age, which corresponds to a number of physiological changes. We related root browning to nitrogen (N) absorption and respiration in order to provide a better understanding of how color changes as typically observed using minirhizotrons relate to changes in root physiology. The experiment was conducted on peach seedlings (Prunus persica cv. ‘Guardian’) grown in 30-L pots in a greenhouse. Brown roots showed lower respiration rates than white roots. White roots showed a higher 15N uptake than brown roots and higher concentration of N, potassium (K), magnesium (Mg), manganese (Mn), iron (Fe) and copper (Cu), no significant differences were observed regarding calcium (Ca), and zinc (Zn) concentration. 相似文献
18.
R. Shahriaripour A. Tajabadi Pour V. Mozaffari H. Dashti E. Adhami 《Journal of plant nutrition》2013,36(8):1166-1179
The effects of four salinity levels [0, 1000, 2000, and 3000 mg sodium chloride (NaCl) kg?1 soil] and three zinc (Zn) levels [0, 5, and 10 mg kg?1 soil as zinc sulfate (ZnSO4.7 H2O)] on growth and chemical composition of pistachio seedlings (Pistacia vera L.) cv. ‘Badami’ were studied in a calcareous soil under greenhouse conditions in a completely randomized design with three replications. After 26 weeks, the dry weights of leaves, stems and roots were measured and the total leaf area determined. Salinity decreased leaf, stem, and root dry weights and leaf area, while this effect diminished with increasing Zn levels. Zn fertilization increased leaf, stem and root Zn concentrations, leaf potassium (K) concentration, and stem and root sodium (Na) concentrations, while decreased leaf Na concentration, and stem and root K concentrations. Salinity stress decreased leaf, stem, and root Zn concentrations, and leaf K concentration, while salinity increased leaf, stem and root Na concentrations, and stem and root K concentrations. Proline accumulation increased with increasing salinity levels, whereas the reverse trend was observed for reducing sugar contents. Zn application decreased proline concentration but increased reducing sugar contents. These changes might have alleviated the adverse effects of salinity stress. 相似文献
19.
Dairy manure (DM) rates of [0 (DM0), 30 (DM30)), 60 (DM60) Mg ha?1] and three nitrogen (N) rates [0 (N0), 125 (N125), 250 (N250) kg ha?1] were tested in a sandy clay loam, to evaluate their effects on growth and yield of wheat crop (Triticum aestivum L.), residual nitrate nitrogen (NO3-N) and phosphorus (P) concentrations in the surface soil, and selected soil physical measurements [saturated hydraulic conductivity (Ksat), and bulk density (BD)]. Increasing N and DM rates gave higher wheat yields, increased concentrations of residual NO3-N and P in the surface soil and improved Ksat and BD. Highest grain yield of 3.8 Mg ha?1 (70.3% more than the control) was observed in DM60 × N250 treatment. Residual accumulation of N-NO3 and P in the surface soil at high N and/or DM application rates suggests the need to carefully manage N and DM inputs on farm fields to avoid environmental contamination. 相似文献
20.
施肥对生土地谷子根苗生长及根际土壤酶和微生物种群的影响 总被引：7，自引：1，他引：6
以黄土母质性生土为供试土壤,采用盆栽试验,探讨了氮、磷、钾及有机肥对谷子生长发育的影响。结果表明:(1)磷是生土地土壤肥力形成与作物生长发育以及根际土壤酶系统和微生物系统形成的首要原始起动营养元素;(2)含磷的处理组合,谷子幼苗阶段地上下部生长均明显较不施磷的长势强,而单施氮和钾甚至不及不施肥的对照。氮、磷、钾对谷子根苗生长的影响顺序为磷氮钾;(3)进入谷子中后期生长阶段,氮素的作用,特别是氮、磷、钾对谷子株高及地上部干重的综合效果表现明显;(4)产量表现为含磷的处理组合,产量及产量结构均明显提高;(5)单施优质高量的有机肥对生土地根苗生长与产量形成具有当年立竿见影的效果;(6)发达的根系促进了根际微生物群落的迅速繁衍,提高了根际土壤酶的活性,有益于促进根-土系统向着熟化方向发展,使生土地上的谷子当年获得正常产量。 相似文献