CAJ | 학술논문

SPAD（ soil-plant analysis and development ）计是一种快速、方便、非破坏性的诊断植物叶片相对叶绿素或氮含量的仪器，与传统的氮营养诊断方法相比，此仪器节省时间、劳力和资源。本试验通过未遮荫和遮荫的方法观察水稻冠层叶片SPAD值、叶绿素含量、叶绿素荧光、光合参数、叶片厚度和比叶重（叶片干重除以叶片的面积）等生理形态指标的变化，建立SPAD值与光系统II（ PSII）最大量子产量（ Fv/Fm）之间的回归关系。结果表明，遮荫条件下，甬优9号（YY9）和丙9363（B9363）冠层叶片变薄、SPAD值、叶绿素a/b、比叶重、电子传递速率（ETR）降低，但快速光曲线的初始斜率无明显变化；同时，遮荫导致了叶片的呼吸速率、最大净光合（ Pmax）、量子效率、光补偿点和饱和点降低，表明水稻叶片为适应弱光环境，降低光合能力、减少呼吸消耗，以增加对有限光能的利用。不同光照条件下，水稻冠层叶片SPAD值与PSII的Fv/Fm的回归方程呈指数式关系（ YY9 R2＝0.896； B9363 R2＝0.833），表明SPAD计可以快速、无损、有效地评估水稻冠层叶片的光合作用进程，当SPAD值小于35时，其光合过程可能处于受损状态。
SPAD（ soil-plant analysis and development ）계시일충쾌속、방편、비파배성적진단식물협편상대협록소혹담함량적의기，여전통적담영양진단방법상비，차의기절성시간、로력화자원。본시험통과미차음화차음적방법관찰수도관층협편SPAD치、협록소함량、협록소형광、광합삼수、협편후도화비협중（협편간중제이협편적면적）등생리형태지표적변화，건립SPAD치여광계통II（ PSII）최대양자산량（ Fv/Fm）지간적회귀관계。결과표명，차음조건하，용우9호（YY9）화병9363（B9363）관층협편변박、SPAD치、협록소a/b、비협중、전자전체속솔（ETR）강저，단쾌속광곡선적초시사솔무명현변화；동시，차음도치료협편적호흡속솔、최대정광합（ Pmax）、양자효솔、광보상점화포화점강저，표명수도협편위괄응약광배경，강저광합능력、감소호흡소모，이증가대유한광능적이용。불동광조조건하，수도관층협편SPAD치여PSII적Fv/Fm적회귀방정정지수식관계（ YY9 R2＝0.896； B9363 R2＝0.833），표명SPAD계가이쾌속、무손、유효지평고수도관층협편적광합작용진정，당SPAD치소우35시，기광합과정가능처우수손상태。
Soil-plant analysis and development (SPAD) meter is a quick, portable,non-destructive diagnostic tool for the measurement of relative chlorophyll or nitrogen ( N) content in leaves.SPAD meter is time, labor and resources saving compared to traditional N nutrition diagnosis methods .The experiment with and without shading treatments was conducted in paddy field with rice cultivars YY 9 and B9363.The physiomorphology indices including leaf SPAD values , chlorophyll contents , chlorophyll fluorescence and photosynthetic parameters , specific leaf weight and blade thickness in rice canopy were measured to establish the regression relationship between SPAD values and the maximum quantum output in photosystem II ( Fv/Fm of PSII) at rice growth stages .The results show that under the shading treatment , there is decline in the leaf SPAD values , chlorophyll a/b ratios, specific leaf weights and electron transport rate .The thickness of leaves becomes thin in rice canopy;the initial slopes of rapid light curves do not change obviously .The respiration rate, the maximum net photosynthetic efficiency (Pmax), the quantum efficiency , light compensation point and saturation point of leaves are decreased to reduce photosynthetic capacity and consume through breath , and increase the utilization of limited light energy under weak light environment .Under both the shading and without shading treatments , exponential relationships exist between the leaf SPAD values and the Fv/Fm of PSII in rice canopy.For cultivar YY9, the coefficient of determination R2 is 0.896 and for B9363 is 0.833.Therefore, the leaf photosynthetic process in rice canopy can be evaluated quickly , non-destructively and efficiently using SPAD meter , and the SPAD reading of lower than 35 may be used to indicate the impairment in photosynthetic process of rice .