葉(ye)片(pian)是(shi)植(zhi)物(wu)光(guang)合(he)作(zuo)用(yong)的(de)主(zhu)要(yao)器(qi)官(guan)

，葉(ye)綠(lv)素(su)是(shi)把(ba)光(guang)能(neng)轉(zhuan)化(hua)為(wei)化(hua)學(xue)能(neng)的(de)重(zhong)要(yao)色(se)素(su)，光(guang)合(he)作(zuo)用(yong)與(yu)葉(ye)片(pian)葉(ye)綠(lv)素(su)含(han)量(liang)之(zhi)問(wen)存(cun)在(zai)著(zhe)密(mi)切(qie)關(guan)係(xi)，葉(ye)片(pian)吸(xi)收(shou)太(tai)陽(yang)輻(fu)射(she)的(de)量(liang)主(zhu)要(yao)由(you)葉(ye)綠(lv)素(su)含(han)量(liang)決(jue)定(ding)，作(zuo)物(wu)葉(ye)片(pian)葉(ye)綠(lv)素(su)含(han)量(liang)可(ke)以(yi)作(zuo)為(wei)葉(ye)片(pian)營(ying)養(yang)狀(zhuang)況(kuang)及(ji)衰(shuai)老(lao)程(cheng)度(du)的(de)參(can)考(kao)依(yi)據(ju)
，葉(ye)片(pian)葉(ye)綠(lv)素(su)含(han)量(liang)的(de)消(xiao)長(chang)規(gui)律(lv)是(shi)反(fan)映(ying)葉(ye)片(pian)生(sheng)理(li)活(huo)性(xing)變(bian)化(hua)的(de)重(zhong)要(yao)指(zhi)標(biao)之(zhi)一(yi)
，了(le)解(jie)和(he)掌(zhang)握(wo)葉(ye)片(pian)的(de)葉(ye)綠(lv)素(su)含(han)量(liang)變(bian)化(hua)規(gui)律(lv)對(dui)於(yu)提(ti)高(gao)作(zuo)物(wu)產(chan)量(liang)具(ju)有(you)重(zhong)要(yao)意(yi)義(yi)。
　　傳統的葉片葉綠素含量測定方法需要進行破壞性取樣，而且需要較長的葉綠素提取時間，比較費工費時，利用葉綠素計能迅速測量作物葉片的葉綠素含量相對值，進行無損營養診斷，其工作原理為：植(zhi)物(wu)葉(ye)綠(lv)素(su)對(dui)光(guang)線(xian)吸(xi)收(shou)的(de)高(gao)峰(feng)在(zai)紅(hong)光(guang)區(qu)和(he)藍(lan)光(guang)區(qu)，而(er)在(zai)綠(lv)光(guang)區(qu)和(he)紅(hong)外(wai)光(guang)區(qu)很(hen)少(shao)，甚(shen)至(zhi)完(wan)全(quan)不(bu)吸(xi)收(shou)。當(dang)用(yong)儀(yi)器(qi)向(xiang)葉(ye)片(pian)的(de)某(mou)部(bu)位(wei)發(fa)射(she)紅(hong)光(guang)和(he)紅(hong)外(wai)光(guang)時(shi)，光(guang)線(xian)透(tou)過(guo)葉(ye)片(pian)被(bei)接(jie)收(shou)器(qi)接(jie)收(shou)後(hou)轉(zhuan)化(hua)成(cheng)電(dian)信(xin)號(hao)，經(jing)放(fang)大(da)和(he)微(wei)處(chu)理(li)器(qi)轉(zhuan)換(huan)成(cheng)．葉綠素值在液晶顯示器上顯示出來，通過數值的大小來定量描述葉片的“綠色度”。近年來，葉綠素計在作物葉片養分的間接速測上應用廣泛，取得了較好的效果，國內在水稻
、小麥筘。玉米
、油菜隅、馬鈴薯、西瓜、黃huang瓜gua等deng作zuo物wu上shang均jun有you研yan究jiu報bao道dao，國guo外wai還hai有you利li用yong葉ye綠lv素su值zhi進jin行xing棉mian花hua氮dan素su養yang分fen遠yuan程cheng遙yao感gan的de報bao道dao。在zai不bu同tong作zuo物wu上shang的de研yan究jiu都dou試shi圖tu找zhao出chu不bu同tong生sheng育yu時shi期qi不bu同tong部bu位wei葉ye片pian葉ye綠lv素su
，葉ye綠lv素su值zhi與yu葉ye片pian、zhizhudanhanliangdeguanxi，congertansuochuyizhongliyongyelvsuzhijinxingkuaisuzhunqueyingyangzhenduandefangfa，yibiangenghaodizhidaoshengchan。wangshaohuarenweidingsiyeshifanyingshuidaodansuyingyangzhuangkuangdelixiangzhishiye，tongshihaifaxiandingsiyeyudingsanyedeyesechayudaozhuhandanliangguanximiqie
，qiebushoupinzhongheshengyuchengduyingxiang
，tichuyongyesechazhidefangfazhenduanshuidaodedansuyingyangzhuangkuang。zhuxinkaitichuyongyelvsuzhilaizhenduanxiaomaiyepiandanhanliangshiyingxuanzewanquanzhankaibingyijinrugongnengshengqideyepian，xiaomaiyepianyelvsuzhiyuyelvsuhanliangxiangguanxingbuxianzhe。jiangbaiwenrenweibeifangchunyumideshangweiyeyelvsufengzhichuxianzaishiyeqi，keyizuoweizhuishidanfeideyiju，yiweizheyumizuidaxufeidedaolai。qiuzhengjundengchaoyanjiuleyoucaicongdingbusuanqidedi3分fen支zhi處chu的de完wan全quan展zhan開kai葉ye綠lv素su含han量liang
，指zhi出chu蕾lei苔tai期qi與yu開kai花hua期qi的de過guo渡du期qi為wei利li用yong葉ye綠lv素su值zhi進jin行xing油you菜cai田tian間jian氮dan肥fei管guan理li和he檢jian測ce的de最zui佳jia時shi期qi。聶nie向xiang榮rong以yi馬ma鈴ling薯shu倒dao三san葉ye的de頂ding小xiao葉ye葉ye綠lv素su值zhi，確que定ding了le不bu同tong時shi期qi進jin行xing推tui薦jian施shi肥fei的de臨lin界jie值zhi。洪hong娟juan指zhi出chu西xi瓜gua苗miao期qi上shang部bu葉ye和he伸shen蔓man期qi下xia部bu葉ye的de葉ye綠lv素su值zhi與yu葉ye片pian含han氮dan量liang均jun有you顯xian著zhe相xiang關guan性xing，可ke將jiang其qi作zuo為wei氮dan營ying養yang診zhen斷duan的de敏min感gan時shi期qi和he敏min感gan部bu位wei。武wu新xin岩yan指zhi出chu黃huang瓜gua正zheng在zai開kai花hua葉ye片pian和he正zheng在zai結jie果guo葉ye片pian的de全quan氮dan含han量liang均jun與yu黃huang瓜gua葉ye片pian的de葉ye綠lv素su值zhi和he硝xiao態tai氮dan的de濃nong度du具ju有you很hen好hao的de相xiang關guan性xing，無wu論lun花hua葉ye還hai是shi果guo葉ye都dou是shi開kai展zhan氮dan素su營ying養yang診zhen斷duan的de主zhu要yao部bu位wei。
　　guoneiguanyumianyeyelvsuhanliangdeyanjiubaodaojiaoduo
，zhijinhudengyanjiuleshuifenhedansuduimianhuayepianyelvsuhanliangdeshikongfenbudeyingxiang，renweizaimianhuashengchangdezhonghouqi
，dishuiliangzhuyaoyingxiangmianhuaxiabuyepianyelvsuhanliang，erdansugongyingliangzhuyaoyingxiangshangbuyepianyelvsuhanliang，zhongbuyepianyelvsuhanliangtongshishoushuifenhedansudetiaojie。guanyumianyeduishidanliangdeminganxingdeyanjiujielunbujinyizhi。lilinglirenweishidanbuzu
，zhujingdaosiyeyelvsuhanliangqianqizengchangdeman，houqishuaijiandekuai，ershidanliangzengjia，yepianyelvsuhanliangqianqizengchangjiakuai
，houqishuaijianbianman，bingweichizaijiaogaoshuiping
，weihouqiyoujiaogaodeguanghesulvdiandingjichu。luoxinningrenweiyelvsuzhiduidansudeminganxingweidaosiyezuigao，daoeryezuidi，erdaoyiye
、倒(dao)三(san)葉(ye)的(de)敏(min)感(gan)性(xing)排(pai)序(xu)因(yin)品(pin)種(zhong)不(bu)同(tong)而(er)不(bu)同(tong)。屈(qu)衛(wei)群(qun)認(ren)為(wei)頂(ding)一(yi)定(ding)型(xing)葉(ye)對(dui)施(shi)氮(dan)量(liang)增(zeng)加(jia)的(de)響(xiang)應(ying)最(zui)為(wei)敏(min)感(gan)，頂(ding)四(si)定(ding)型(xing)葉(ye)最(zui)為(wei)遲(chi)鈍(dun)。利(li)用(yong)頂(ding)一(yi)定(ding)型(xing)葉(ye)與(yu)頂(ding)四(si)定(ding)型(xing)葉(ye)駢(pian)MD值的相對差值，可較精確地診斷棉花的氮素營養水平，並能克服品種和生育時期不同的影響。郝俊傑將開花後35天和開花當天倒四葉的葉綠素的差值作為診斷棉花葉片早衰的指標。鄔飛波獲得了短季棉不同生育時期棉花主莖功能葉(倒數第3~4主莖葉)葉綠素診斷指標。汪玲等啦伽研究認為主莖倒四葉綠素。葉綠素值在蕾期、初花期、盛花期
、花鈴期
、盛鈴期的積累值與產量之間存在明顯的正相關。
     葉片葉綠素含量變化規律取得如此巨大的成果，很在層度上歸功於葉綠素計在研究中的應用，使得科研人員對葉綠素的測量變的更加的方便和準確。