CAJ | 학술논문

【目的】临界氮浓度是指在一定的生长时期内获得最大生物量时的最小氮浓度值,具有明确的生物学意义。探究不同水氮供应对番茄地上部生物量、氮素累积的影响,构建临界氮浓度稀释曲线模型,并基于氮素吸收和氮营养指数模型进行番茄氮素营养诊断,可为番茄水肥一体化提供一定的理论依据。【方法】于2013年在日光温室内进行了盆栽试验,供试番茄品种为金鹏M6088。设置3个灌水量为低水 W1(60%70%θf )、中水 W2(70%80%θf)和高水 W3(80%90%θf),θf 为田间持水率；施氮量设置3个水平为低氮 N1(N 0．24 g/kg土)、中氮 N2(N 0．36 g/kg土)和高氮N3(N 0．48 g/kg土),试验采用完全随机区组设计,共9个处理,每个处理重复15次,研究了不同水氮条件下番茄的地上部生物量、氮素累积及氮浓度的动态变化,构建了番茄不同水分条件下的临界氮浓度稀释曲线模型。【结果】番茄地上部生物量、氮累积量随移栽时间的动态变化符合Logistic模型,不同水氮供应对番茄地上部生物量理论最大值的影响不同,中水和高水条件下,番茄地上部生物量理论最大值随着施氮量的增加呈先增加后减小的趋势；而在低水条件下呈递增趋势,说明适量增施氮肥可以减轻干旱对干物质量累积的抑制；番茄地上部生物量快速累积起始日较氮快速累积起始日晚817 d,且不同水氮处理番茄地上部生物量最大生长速率、氮累积量最大累积速率均出现在中水中氮( W2 N2)处理；在相同的水分条件下,番茄地上部生物量氮浓度随施氮量的增加而提高,随生育进程的推移呈下降趋势；氮浓度与地上部生物量之间符合幂指数关系,适当增大灌水量可以提高植株对氮的容纳能力,并且可以缓解氮浓度随植株生物增长量下降,使植株稳步有序地生长；不同的水氮供应对番茄产量影响显著,随着灌水量和施氮量的增加,产量显著提高,但当灌水量和施氮量达到一定数量时产量不仅没有提高反而随其增加而降低。【结论】基于临界氮浓度构建的氮营养指数、氮吸收模型对番茄的适宜施氮量诊断结果一致,均以中水中氮(W2N2)为最佳条件,即当灌水量和施肥量分别为62．1 L/plant、15．1 g/plant时,番茄单株产量达到最大(1602 g),构建的模型合理可行。【目的】臨界氮濃度是指在一定的生長時期內穫得最大生物量時的最小氮濃度值,具有明確的生物學意義。探究不同水氮供應對番茄地上部生物量、氮素纍積的影響,構建臨界氮濃度稀釋麯線模型,併基于氮素吸收和氮營養指數模型進行番茄氮素營養診斷,可為番茄水肥一體化提供一定的理論依據。【方法】于2013年在日光溫室內進行瞭盆栽試驗,供試番茄品種為金鵬M6088。設置3箇灌水量為低水 W1(60%70%θf )、中水 W2(70%80%θf)和高水 W3(80%90%θf),θf 為田間持水率；施氮量設置3箇水平為低氮 N1(N 0．24 g/kg土)、中氮 N2(N 0．36 g/kg土)和高氮N3(N 0．48 g/kg土),試驗採用完全隨機區組設計,共9箇處理,每箇處理重複15次,研究瞭不同水氮條件下番茄的地上部生物量、氮素纍積及氮濃度的動態變化,構建瞭番茄不同水分條件下的臨界氮濃度稀釋麯線模型。【結果】番茄地上部生物量、氮纍積量隨移栽時間的動態變化符閤Logistic模型,不同水氮供應對番茄地上部生物量理論最大值的影響不同,中水和高水條件下,番茄地上部生物量理論最大值隨著施氮量的增加呈先增加後減小的趨勢；而在低水條件下呈遞增趨勢,說明適量增施氮肥可以減輕榦旱對榦物質量纍積的抑製；番茄地上部生物量快速纍積起始日較氮快速纍積起始日晚817 d,且不同水氮處理番茄地上部生物量最大生長速率、氮纍積量最大纍積速率均齣現在中水中氮( W2 N2)處理；在相同的水分條件下,番茄地上部生物量氮濃度隨施氮量的增加而提高,隨生育進程的推移呈下降趨勢；氮濃度與地上部生物量之間符閤冪指數關繫,適噹增大灌水量可以提高植株對氮的容納能力,併且可以緩解氮濃度隨植株生物增長量下降,使植株穩步有序地生長；不同的水氮供應對番茄產量影響顯著,隨著灌水量和施氮量的增加,產量顯著提高,但噹灌水量和施氮量達到一定數量時產量不僅沒有提高反而隨其增加而降低。【結論】基于臨界氮濃度構建的氮營養指數、氮吸收模型對番茄的適宜施氮量診斷結果一緻,均以中水中氮(W2N2)為最佳條件,即噹灌水量和施肥量分彆為62．1 L/plant、15．1 g/plant時,番茄單株產量達到最大(1602 g),構建的模型閤理可行。
【목적】림계담농도시지재일정적생장시기내획득최대생물량시적최소담농도치,구유명학적생물학의의。탐구불동수담공응대번가지상부생물량、담소루적적영향,구건림계담농도희석곡선모형,병기우담소흡수화담영양지수모형진행번가담소영양진단,가위번가수비일체화제공일정적이론의거。【방법】우2013년재일광온실내진행료분재시험,공시번가품충위금붕M6088。설치3개관수량위저수 W1(60%70%θf )、중수 W2(70%80%θf)화고수 W3(80%90%θf),θf 위전간지수솔；시담량설치3개수평위저담 N1(N 0．24 g/kg토)、중담 N2(N 0．36 g/kg토)화고담N3(N 0．48 g/kg토),시험채용완전수궤구조설계,공9개처리,매개처리중복15차,연구료불동수담조건하번가적지상부생물량、담소루적급담농도적동태변화,구건료번가불동수분조건하적림계담농도희석곡선모형。【결과】번가지상부생물량、담루적량수이재시간적동태변화부합Logistic모형,불동수담공응대번가지상부생물량이론최대치적영향불동,중수화고수조건하,번가지상부생물량이론최대치수착시담량적증가정선증가후감소적추세；이재저수조건하정체증추세,설명괄량증시담비가이감경간한대간물질량루적적억제；번가지상부생물량쾌속루적기시일교담쾌속루적기시일만817 d,차불동수담처리번가지상부생물량최대생장속솔、담루적량최대루적속솔균출현재중수중담( W2 N2)처리；재상동적수분조건하,번가지상부생물량담농도수시담량적증가이제고,수생육진정적추이정하강추세；담농도여지상부생물량지간부합멱지수관계,괄당증대관수량가이제고식주대담적용납능력,병차가이완해담농도수식주생물증장량하강,사식주은보유서지생장；불동적수담공응대번가산량영향현저,수착관수량화시담량적증가,산량현저제고,단당관수량화시담량체도일정수량시산량불부몰유제고반이수기증가이강저。【결론】기우림계담농도구건적담영양지수、담흡수모형대번가적괄의시담량진단결과일치,균이중수중담(W2N2)위최가조건,즉당관수량화시비량분별위62．1 L/plant、15．1 g/plant시,번가단주산량체도최대(1602 g),구건적모형합리가행。
[Objectives] The critical nitrogen ( N ) concentration in plant aboveground biomass is defined as the minimum N concentration required for maximum plant growth. This study investigated the effects of different water and nitrogen supply on tomato aboveground biomass, nitrogen accumulation, and drew a critical N concentration dilution curve. The N status of tomato plant was analyzed based on a model of N uptake and nitrogen nutrition index ( NNI ) , which provided a theoretical basis for optimal water and nitrogen management. [Methods]A pot experiment was conducted in greenhouse of the Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Area of Ministry of Education in Northwest Agriculture and Forestry University in 2013 . Cultivar of tomato(M6088)was used in this experiment. The treatment comprised three levels of irrigation(W1, 60%-70% θf;W2, 70%-80% θf;W3, 80%-90% θf),θf is the field capacity, and three levels of nitrogen(N1, N 0. 24 g/kg;N2, N 0. 36 g/kg;N3, N 0. 48 g/kg). For determining the critical N concentration dilution curves under different water conditions, the treatments were replicated fifteen times in random complete block designs to examine the dynamic changes of tomato aboveground biomass and nitrogen accumulation under different water and nitrogen conditions. [Results] The aboveground biomass and N accumulations presented a Logistic curve over time. Different water and nitrogen supply had different effects on maximum theoretical value of tomato aboveground biomass:the maximum theoretical value of tomato aboveground biomass increased firstly and decreased with the increase of nitrogen rate under two levels of irrigation ( W2 , W3 ) . It also increased with the increase of nitrogen rate under the level of irrigation(W1), which indicated that moderate nitrogen supply could enhance the inhibiting effect of drought on aboveground biomass accumulation of tomato. The beginning time of fast accumulation period for nitrogen was 8-17 days earlier than those for biomass, the maximum accumulation rates of tomato aboveground biomass and nitrogen were both found in W2N2 treatment. Under the same water supply condition, the nitrogen concentration of tomato aboveground biomass increased with the improving of applied N rates, and decreased in the growing process. The relationship between the aboveground biomass and N concentration could be described by the power equation, appropriate irrigation could improve the capacity of plant for nitrogen absorption and relieved the decline of nitrogen concentration with the aboveground biomass growth to ensure a steady and orderly growth of tomato. The yield was significantly affected by water and nitrogen supply, appropriate condition of water and nitrogen achieved maximum yield. [Conclusions] Based on the model of nitrogen nutrition( NNI) and the model of N uptake, the W2N2 treatment was the optimal option with irrigation amount of 62. 1 L/plant, nitrogen rate of 15. 1 g/plant, and the highest yield was 1602 g/plant. Thus, the models built in this study were reasonable and feasible for the research objectives.