Preliminary Report on the Mineral Composition of Papaya Soil and Plant Tissue in Puna, Hawaii Under Different Land Use Practices

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1 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties CHANTAL VOS 1* AND ALYSSA CHO 2 1 University of Hwii t Hilo, College of Agriulture, Forestry nd Nturl Resoure Mngement, Hilo, HI, USA. 2 University of Hwii t Mno, College of Tropil Agriulture nd Humn Resoures, Komohn Reserh Extension Center, Hilo, HI, USA. Astrt: Ppy growers in Hwii fe poor fruit yields nd rising prodution osts. Current lnd use prties, suh s fertiliztion nd lnd lering my e unsustinle nd e the use of these delining yields. To identify the effet of ppy ultivtion, lnd lering, nd fllow under ttle-grzed psture, the nutrient omposition of soil nd plnt tissue ws ompred t five sites (virgin, medium-ultivted, ndoned, erm, nd psture). Soil ph ws elow the optimum rnge for ppy rops t ll tested sites. Soil phosphorus (P) levels were high t medium, erm, nd ndoned sites, nd low t the virgin nd psture sites. Soil potssium (K) levels were low t ll sites. Soil lium (C) nd mgnesium (Mg) levels were low t the medium, ndoned nd psture sites nd high t the virgin nd erm sites. Medium nd ndoned sites hd signifintly lower soil ph, ron (C), C, nd Mg levels ompred with virgin nd erm sites. No signifint differene ws found in soil nitrogen (N) nd K etween these sites. Soil P levels were signifintly higher t medium, erm, nd ndoned sites ompred with virgin nd psture sites. Cttle-grzed psture hd signifintly higher onentrtions of soil C nd N thn the ndoned field. No signifint differenes in soil ph, P, K, C, nd Mg were found etween psture nd ndoned sites. Berm sites hd signifintly higher soil ph, C, K, C, nd Mg levels ompred with djent medium sites. Differenes in soil omposition etween sites were likely relted to soil C, mesure for soil orgni mtter. Signifint orreltions were found etween soil C nd soil N, K, C, nd Mg. Tissue N, P, K, nd sulfur (S) were signifintly higher t the virgin site ompred with medium, erm, nd ndoned sites, ut this ws likely relted to plnt ge t the time of smpling. Petioles olleted from the virgin site hd high N, P, nd K, low C, nd dequte Mg nd S levels. The medium site hd low N, P, C, nd S, nd dequte K nd Mg levels. The ndoned site hd high Mg levels, nd low N, P, K, C, nd S levels. The erm site hd high K, dequte N nd Mg, nd low P, C, nd S levels. These preliminry results demonstrte tht urrent lnd use prties re unsustinle nd led to deresing soil fertility nd low plnt nutrient levels. Preserving nd inresing soil orgni mtter should ply key role when mking hnges to urrent lnd use prties. Key words: Ppy, Lnd use prties, Nutrient mngement Introdution Mny ppy growers in Hwii struggle to mke profit. Low yields, high input nd lor osts, pest nd disese prolems, stringent regultions, nd foreign ompetition pose hllenges to ppy frmers (Evns et l., 2015). Ppy yields in the Pun Distrit, the min ppy prodution re in Hwii, were seriously ffeted y the ppy ringspot virus (PRSV) etween 1992 nd 1998 (Mnshrdt, 2012). Annul yields deresed from 29.5 to 18.8 thousnd pounds per re during the virus outrek (USDA-ERS, 2015). In 1998, the genetilly modified (GM) PRSV-resistnt Rinow hyrid ws relesed nd widely dopted y ppy frmers (Mnshrdt, 2012). Yields inresed to 33 thousnd pounds per re in 2000 *Corresponding uthor, e-mil: vos@hwii.edu 1 P. Agri. Nt. Resour.

2 2 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties (USDA-ERS, 2015). However, sine 2001 yields hve een delining. In 2013 nd 2014, ppy yields were 18.6 nd 15.7 thousnd pounds, respetively, whih is lower thn during the PRSV outrek (USDA-ERS, 2015). These delining fruit yields re likely the result of existing lnd use prties, suh s fertilizer pplitions nd lnd lering tehniques. Prodution dt from ppy growers in the Pun Distrit demonstrte lrge differenes in yield nd fruit qulity etween frmers, despite utiliztion of fields in ner proximity. These yield nd qulity differenes re likely used y vritions in ulturl prties of the individul frmer, suh s fertilizer nd pestiide pplitions. Due to inresing pries, fertilizers nd other hemils re not lwys pplied t reommended levels. Current lnd lering tehniques my lso indiretly led to delining yields. It is ommon prtie to ndon ppy fields fter four to five yers of prodution, due to high disese pressure nd redued soil fertility. After eing left fllow, the lnd is lered efore plnting y ulldozing ll volunteer vegettion into lrge erm. Using this tehnique, lrge mounts of top soil re unintentionlly pushed from the plnting re nd left in erms t the edges of the fields. Ppy trees growing on these erms were oserved to e higher yielding thn ppy trees grown in the lered field (Pers. Os.). Rottions, suh s ttle-grzed psture or rop rottions my provide n lterntive for the need to ler the lnd fter eing left fllow. Approprite lnd use prties ould improve yields nd fruit qulity nd ould potentilly led to higher revenues for Hwiin ppy frmers. The ojetive of this study ws to identify the effet of ppy ultivtion, lnd lering, nd fllow under ttle-grzed psture on the nutrient omposition of soil nd plnt tissue in ppy prodution system. Mterils nd Methods Lotions The tril egn in June 2015 within Shipmn Industril Prk (19 37 N, W) t 161 m elevtion ner Keu, Hwii. Averge nnul rinfll is 3,874 mm nd the verge dily temperture is 21.7 C. Soils re lssified s Ppi, extremely oly muk (Eui, isohyperthermi Typi Udifolists) with highly deomposed plnt mteril. These soils re well-drined nd hve thin lyer of orgni mteril over frgmentl `` lv sustrt. Between June nd Deemer 2015, soil nd tissue smples were olleted from four lotions, whih were seleted sed on lnd use prties. These lotions were: virgin lnd, medium-term ultivted lnd, ndoned (longterm ultivted) lnd, nd ttle-grzed psture. Virgin lnd This site ws not previously ultivted nd ws lered in April Ppy rops were plnted in fields in the sme yer. This site will e referred to in this report s virgin. Within the virgin site, four susites were seleted sed on good nd onsistent fruit prodution of the frmer lesing the field. The lotion of eh susite is represented y yellow dots in Figure 1. Soil smples were olleted etween plnting rows t depth of 1-3 inhes from 10 to 15 lotions within eh susite nd mixed together to mke omposite smple. Ppy petioles were olleted from 15 trees rndomly seleted throughout eh susite. The most reently mture lef ws hrvested s reommended y Tmimi et l. (1997). At the time of smpling, the ppy rops were pproximtely three months old nd t the vegettive growth stge. Petioles olleted from vegettive ppy rops will generlly show higher minerl onentrtions nd will therefore not e ompred with petioles from fruit-ering ppys t other sites. Medium-ultivted lnd This lotion ws previously ultivted with ppy rops during two prodution yles nd lst lered in Mrh Ppys trees were pproximtely 18 months old nd ering fruit t the time of smpling. Soil nd petiole smples were olleted from 8 regulr ppy fields ( medium ) nd 4 erm sites ( erm ) djent to these fields. The lotion of medium susites (yellow dots) nd erm sites (lue dots) is represented in Fig 1. Soil smples were olleted etween plnting rows. Petioles were olleted from leves under the most reently set fruit sed on the reommendtions from Nishin et l. (2000) nd Uhid (2000). Andoned lnd This lotion ws previously ultivted with ppy rops for t lest three prodution yles nd sine mid-2015 ws no longer in use for ommeril fruit prodution. This site will e referred to s ndoned. Until Septemer 2015, ndoned fruit-ering ppy trees remined in the field. Five P. Agri. Nt. Resour.

3 Chntl Vos nd Alyss Cho 3 susites were seleted, four of these hd fruitering ppy trees. Soil nd petiole smples were olleted in Septemer Petioles were olleted from leves under the most reently set fruit. Soil smples were olleted etween rows. Between Novemer nd Deemer, the ndoned trees were removed. In Deemer 2015 dditionl soil smples were olleted ner the remining trunks to quntify residul fertilizer. Fig. 1. Lotion of smpling sites. Yellow dots represent the enter of susite. Blue dots represent erm sites. The totl shded re is pproximtely 600 h. Cttle-grzed psture lnd Cttle-grzed psture ws inluded s site to evlute if nd to wht extent psture n restore depleted soils nd to determine if this site is suitle for ppy ultivtion t this lotion. This re ws formerly used for ommeril sugrne ultivtion, whih is known to deplete soil orgni mtter in similr mnner s intensive ppy prodution (Osher et l., 2003). This re ws onverted to ttle-grzed psture round Soil smples were olleted from nine different su-sites (Fig. 1). Smple proessing nd nlysis Plnt tissue Ppy petioles were hrvested from 10 to 15 ppy plnts within eh susite. Tissue smples were oven-dried for t lest 72 hours t 60 C nd ground in Wiley mill to pss 1 mm sieve. Tissue smples were nlyzed for minerls y Wters Agriulturl Lortories In. Cmill, Georgi. Soil Soil smples were olleted t depth of 1-3 inhes from 10 to 15 lotions within eh susite nd were mixed together to mke omposite smple. The omposite soil smple ws sieved to pss 5 mm sreen. To void fertilizer ontmintion, smples were olleted etween rows nd not within rows. Soil smples were nlyzed for ph, totl ron (C), nd extrtle mronutrients y the Agriulturl Dignosti Servie Center of the College of Tropil Agriulture nd Humn Resoures of the University of Hwii t Mno. P. Agri. Nt. Resour.

4 4 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties Sttistil nlysis Anlysis of vrine (ANOVA) ws onduted using PROC GLM in SAS softwre (SAS Institute In., Cry, NC). Nutrient omposition dt from virgin, medium, erm, ndoned nd psture sites were ompred. were onsidered tretments nd susites were onsidered replitions. Mens were seprted using Dunn s multiple rnge where proility level of 0.05 or less ws onsidered to e sttistilly signifint. Correltion nlysis ws performed using in SAS softwre on soil dt from virgin, medium, ndoned, erm, nd psture sites. Person orreltions were onsidered signifint t proility level of 0.05 or less. Soil nutrient omposition dt from ndoned susites were ompred etween rows nd lose to tree stumps. ANOVA ws onduted using PROC GLM in SAS softwre (SAS Institute In., Cry, NC). Smple lotions ( etween rows nd lose to tree stump ) were onsidered tretments nd susites were onsidered replitions. Mens were seprted using Dunn s multiple rnge where proility level of 0.05 or less ws onsidered to e sttistilly signifint. Results nd Disussion Soil Soil ph, ron (C), nitrogen (N), phosphorus (P), potssium (K), lium (C), nd mgnesium (Mg) vlues re represented s the mens t five sites in Figure 2. Columns leled with the sme letters re not signifintly different (P>0.05). Error rs represent the stndrd error of mens. Dshed horizontl lines re the oundries of the reommended rnge for lnd soils from Tmimi et l. (1997). Soil ph Soil ph influenes the vilility of plnt nutrients. A soil ph etween 5.5 nd 6.2 is onsidered dequte for lnd soils, however, the optimum soil ph for ppy rops is etween 5.8 nd 6.5 (Tmimi et l., 1997; Uhid nd Hue, 2000). Soil ph ws lower thn the reommended rnge t ll of the sites exept for the virgin nd erm site (Fig. 2). All sites hd ph elow the optimum for ppy rops. Lime pplitions re reommended to redue lehing of K, C, nd Mg, nd inrese the vilility of plnt nutrients. Soil ph ws signifintly (p<0.05) lower t medium nd ndoned sites ompred with virgin nd erm sites, inditing tht medium to long-term ppy ultivtion in fields dereses soil ph. The psture site hd signifintly higher soil ph thn the medium ppy field. Cttle-grzed psture ould potentilly inrese soil ph s prt of rottion with ppy rops. Soil ron Soil orgni mtter plys ruil role in improving soil struture, supply of mro- nd mironutrients, soil miroorgnisms nd iodiversity. Soil ron onentrtions, mesure for orgni mtter, re represented in Fig 2. C levels were signifintly (p<0.05) greter t virgin nd erm sites ompred with medium nd ndoned sites. Psture hd signifintly (p<0.05) higher C levels ompred with the ndoned site. Aording to these results, medium to long-term onventionl ppy ultivtion dereses soil C. Psture over my hve enefiil effet on soil orgni mtter s prt of rottion with ppy rops. Soil C showed signifint (p<0.05) orreltions with soil N (r = 0.84), K (r = 0.38), C (r = 0.61), nd Mg (r = 0.64). Current lnd lering prties remove lrge mounts of topsoil from the plnting re. The lyer of soil orgni mtter in lnd soils is thin nd onentrted in the top soil. Retention nd restortion of soil orgni mtter in the ppy field n help to mintin the pility of the soil to stilize N, C, nd Mg, nd to lesser extent K ginst lehing (Mthews nd Senok, 1998). Sustinle griulturl mngement strtegies, inluding over rops, green mnure, nd niml mnure, n inrese soil orgni mtter levels over those typil of onventionl intensive griulture with the ssoited inrese in soil fertility nd wter-holding pity (Mtson et l., 1997). P. Agri. Nt. Resour.

5 Chntl Vos nd Alyss Cho 5 Soil ph Soil C (%) Soil N (%) Soil P (ppm) Soil K (ppm) Soil C (ppm) Soil Mg (ppm) Fig. 2. Soil ph, ron (C), nitrogen (N), phosphorus (P), potssium (K), lium (C), nd mgnesium (Mg) vlues re represented s the mens t virgin (V), medium (M), erm (B), ndoned (A), nd psture (P) sites. Columns leled with the sme lowerse letters re not signifintly different (P>0.05). Error rs represent the stndrd error of mens. Dshed horizontl lines re the oundries of the reommended rnge for lnd soils from Tmimi et l. (1997). P. Agri. Nt. Resour.

6 6 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties Soil nitrogen Soil nitrogen (Fig. 2) ws signifintly (p<0.05) higher t the erm (0.75%) nd psture (0.70%) sites ompred with the ndoned site (0.36%). N levels t virgin (0.57%) nd medium (0.53%) sites were not signifintly different from erm, ndoned nd psture sites. Soil N vlue from ll tested sites demonstrted strong (p<01) orreltion with soil C. High rinfll (3874 mm nnully) t the smpling sites with soils n led to onsiderle nitrogen (N) lehing. Aording to Mthews nd Senok (1998), 200 mm of rin n leh 50% of the N pplied s mmonium slts from the topsoil, therefore N-fertilizer, preferly slow-relese, should e pplied in split pplitions, espeilly during hevy rin events. Soil phosphorus Soil P levels (Fig. 2) were ove dequte levels ( ppm) t the medium (287 ppm), erm (397 ppm), nd ndoned (295 ppm) site. This my e the result of fertilizer pplitions, s soils re not nturlly high in P. Medium, erm, nd ndoned sites hd signifintly higher P levels thn virgin nd psture sites. Soil P levels t virgin (16 ppm) nd psture (27 ppm) sites were well elow the reommended levels. The virgin site ws reently lered nd hd not reeived s muh fertilizer s the medium- nd long-term ultivted lnd. The psture site ws not fertilized. Soil potssium Soil K onentrtions (Fig. 2) were well elow reommended levels t ll sites. This indites soil K depletion through plnt uptke nd lehing. Prent mteril of Ppi soils is generlly low in K, therefore minerliztion is not n importnt K soure. Split pplitions of K re reommended for ll ppy prodution sites in this study. Soil K showed signifint (p = 0.037) orreltion with soil orgni ron (r = 0.38), inditing tht preserving nd inresing soil orgni mtter my inrese plnt ville K. Using residues of deeprooted interrops s mulh my reover K lehed into deeper soil levels. Soil lium Soil C levels (Fig. 2) were elow the reommended levels t medium (859 ppm), ndoned (507 ppm), nd psture (610 ppm) sites. Soil C levels t virgin (2151 ppm) nd erm (2893 ppm) sites were ove the reommended levels. The erm site hd signifintly (p<0.05) higher soil C levels thn ll other tested sites. Soil C t the virgin site ws signifintly (p<0.05) greter thn t the medium, ndoned nd psture sites. Soil lium showed signifint orreltion (r = 0.61) with soil ron. Soil orgni mtter hd positive effet on plnt ville C. Inresing soil orgni mtter nd lime pplitions re reommended to inrese lium nd soil ph. Solule gypsum n e pplied for immedite orretion of lium defiienies, ut hs little effet on soil ph. Soil mgnesium Soil Mg levels (Fig. 2) were elow the dequte rnge for medium (204 ppm), nd ndoned (144 ppm) sites. Soil Mg t the psture (308 ppm) site ws on the low end of the reommended rnge. Virgin (597 ppm) nd erm (955 ppm) sites hd soil Mg levels ove the reommended rnge. The erm site hd signifintly (p<0.05) higher soil Mg levels thn ll other tested sites. Soil Mg t the virgin site ws signifintly (p<0.05) greter thn t the medium, ndoned nd psture sites. Soil Mg showed signifint orreltion (r = 0.64) with soil ron. Soil orgni mtter hd positive effet on plnt ville Mg. Soil Mg showed strong (p<01, r = ) orreltion with soil C. Residul fertilizer t ndoned site To determine if lolized mounts of fertilizer remin in the soil fter fllowing ppy field, dditionl soil smples were olleted t the ndoned sites. Soil smples were olleted ner the remins of the ppy trunks nd ompred with smples olleted etween rows. Smples olleted ner ut-down ppy stumps t the ndoned sites hd higher (p<0.05) soil ph, N%, C%, nd K (ppm) levels thn smples olleted etween rows (Tle 1). These results indite tht lolized mounts of residul N nd K fertilizer remin in the soil fter fllowing ppy fields. Soil P ws not signifintly different etween smple lotions due to lrge stndrd error used y n extremely high soil P level (1489 ppm) t one of the smpled susites. P. Agri. Nt. Resour.

7 Chntl Vos nd Alyss Cho 7 Tle 1. Soil ph nd nutrient omposition t the ndoned site etween rows nd lose to the tree stump. Dt represent mens of five su-sites. Smple Lotion ph N % C % P ppm K ppm C ppm Mg ppm Between rows Close to tree stump Mens within the sme olumn followed y ommon letter re not different t P<0.05. One-wy ANOVA. Tissue Tissue nitrogen (N), phosphorus (P), potssium (K), lium (C), mgnesium (Mg), nd sulfur (S) vlues re represented s the mens etween four ppy ultivtion sites (Fig. 3). Columns leled with the sme letters re not signifintly different (P>0.05). Error rs represent the stndrd error of mens. Dshed horizontl lines re the oundries of the suffiieny rnge for ppy petioles olleted under the most reent set fruit (Uhid, 2000; Nishin, 2000). At the time of smpling, the ppy rops t the virgin site were pproximtely three months old nd t the vegettive growth stge. Petioles were olleted from the most reent mture lef s reommended y Tmimi (1997). Ppy trees t the medium, erm, nd ndoned sites were ering mture fruits. Petioles olleted from vegettive ppy rops will generlly show higher minerl onentrtions thn fruit-ering ppys. Tissue nitrogen Tissue N levels (Fig. 3) were elow the suffiieny rnge t the medium (1.12%) nd ndoned (1.04%) sites. Tissue N levels t the erm (1.26%) site were within dequte levels. Tissue N t the virgin site ws 1.94%, whih is signifintly higher thn the other sites. As disussed erlier, this is likely used y the growth stge of ppy trees t the virgin site t the time of smple olletion. No signifint differenes in petiole N onentrtions were found etween medium, erm, nd ndoned sites. Awd nd Sueshis (1975) reommend petiole N level t 1.28% N for ppy growers in Pun. This vlue is ssoited with 95% of the mximum ttinle fruit yield. N-fertilizer rtes of 136 g per tree every 12 weeks were ssoited with this fruit yield. Of the tested sites, N fertilizer is reommended for the medium ppy fields. Tissue phosphorus Tissue P onentrtions (Fig. 3) were elow the reommended rnge t the medium (0.16%), erm (0.16%), nd ndoned (0.13%) sites. Tissue P t the virgin site ws 0.35%, whih is signifintly higher thn the other sites. As previously mentioned, this ws likely due y the growth stge of ppy trees t the virgin site t the time of smple olletion. High soil P levels found t the test sites were not refleted in high tissue P levels. This indites tht soil P ws not ville for uptke y the ppy roots. P moves only short distnes in the soil nd must e ner the root for sorption. A limited volume of soil to whih roots hve ess in roky soils my e limiting P uptke. Phosphorus defiieny n use poor root development therey further inresing the prolem. Ppy plnts re highly dependent on symioti ssoitions with soil fungi. Fungl hyphe inrese the volume of soil tht plnt roots explore nd n enhne P sorption (Mthews nd Senok, 1998; Hte nd Osorio, 2001; Miyski et l., 2003). Sukrno et l. (1993) found tht the use of some fungiides redues the rusulr myorrhizl fungi in the soil. Conventionl ppy prties onsist of preventive sprying with fungiides suh s Mnzte, Koide 3000, nd Aound Flowle t 2 to 3 week intervls. Further reserh is needed to determine if these fungiides hve n effet on enefiil soil fungi or if low tissue P hs different use. P. Agri. Nt. Resour.

8 8 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties Tissue N (%) Tissue P (%) Tissue K (%) Tissue C (%) Tissue Mg (%) Tissue S (%) Fig. 3. Tissue nitrogen (N), phosphorus (P), potssium (K), lium (C), mgnesium (Mg), nd sulfur (S) vlues re represented s the mens t virgin (V), medium (M), erm (B), nd ndoned (A) sites. Columns leled with the sme lowerse letters re not signifintly different (P>0.05). Error rs represent the stndrd error of mens. Dshed horizontl lines indite the upper nd lower oundries of the suffiieny rnge for ppy petioles olleted under the most reent set fruit (Nishin, 2000; Uhid, 2000). Tissue potssium Tissue K levels (Fig. 3) were ove the reommended rnge t virgin (5.21%) nd erm (3.71%) sites; within the rnge t the medium (2.88%) site; nd elow the rnge t the ndoned (1.10%) site. Tissue K ws signifintly (p<0.05) higher t the virgin site ompre to ll other sites. The ndoned site hd signifintly (p<0.05) lower tissue K levels ompred with ll other sites. Soil K levels were low for ll sites. Soil smples were olleted etween rows to void fertilizer ontmintion. Tissue K levels possily reflet K- fertilizer pplitions ner the tree. Tissue lium Tissue C onentrtions (Fig. 3) were low for ll sites. Tissue C ws signifintly higher t the erm (1.00%) site ompred with the virgin (0.79%) nd medium (0.84%) sites, ut not signifintly higher thn the ndoned (0.96%) site. Tissue C generlly inreses with plnt ge (Mills nd Jones, 1996), whih my explin why petioles t the virgin site hd low tissue C t high soil C levels. P. Agri. Nt. Resour.

9 Chntl Vos nd Alyss Cho 9 Clium plys n essentil role in post-hrvest fruit qulity, ripening nd shelf life (Qiu et l., 1995). Clium pplitions re reommended for ll sites. Tissue mgnesium Tissue Mg onentrtions (Fig. 3) were within the dequte rnge for ll sites. Petioles from the ndoned site hd signifintly higher (p< 0.05) Mg onentrtion thn the other sites. Tissue Mg generlly inreses with plnt ge (Mills nd Jones, 1996), whih my explin the higher tissue Mg level t the ndoned site. Tissue sulfur Tissue S onentrtions (Fig. 3) were elow the reommended rnge t the medium (0.18%), nd erm (0.19%) sites. Tissue S ws signifintly (p<0.05) higher t the virgin site ompred with ll other sites. S fertiliztion is reommended for the medium nd erm sites. Gypsum is good soure for oth lium nd sulfur. Tissue mironutrients Tissue oron onentrtions were elow reommended levels (20-50 ppm) in petioles from medium (17 ppm), erm (18 ppm), nd ndoned (16 ppm) sites. Tissue oron levels t the virgin site (25 ppm) were signifintly higher thn the other sites. Boron defiienies n use fruit deformities in ppy. Boron pplitions re reommended for the medium nd erm sites. Tissue zin onentrtions were within dequte levels, exept t the ndoned site. Mngnese ws within dequte levels. Iron onentrtions were norml t the erm site, nd ove the reommended levels t the virgin, medium, nd ndoned sites. A lrge vrition ( ppm) in tissue iron ws found. Tissue opper onentrtions were ove the dequte rnge for ll sites, whih my e relted to the use of opper s fungiide. More tissue smpling is needed to dequtely dignose the mironutrient sttus of ppy rops t different rottionl stges. Conlusions Preliminry results disussed in this report demonstrte tht onventionl lnd use prties t the medium nd ndoned sites hve led to low soil ph nd low soil fertility. Plnt nutrient levels were generlly low. These results indite tht urrent fertilizer pplitions do not ompenste for the soil minerl depletion used y lnd lering, hrvesting, nd lehing. Soil fertility ws higher t the erm site ompred with the medium site. Berm sites hd signifintly higher ph, soil C, K, C, nd Mg ompred with medium ppy fields, inditing tht lnd lering removes plnt ville nutrients from the field. Cttle-grzed psture hd signifintly higher soil C nd N thn the ndoned field, ut did not inrese soil ph, P, K, C, or Mg. Inresing ppy yields in sustinle mnner requires djustments to the urrent nutrient mngement prties. Imported fertilizers re expensive due to shipping osts nd ffordle lol fertilizers re not ville in suffiient quntities. Soil orgni mtter is ruil in improving soil struture, supply of nutrients, soil miroorgnisms nd iodiversity. Preserving nd inresing soil orgni mtter should ply key role when mking hnges to urrent lnd use prties. There is growing interest in low-ost orgni prodution methods suh s nturl frming. These methods re sed on the ssumption tht inresing the mount, tivity, nd diversity of indigenous soil miroorgnisms s well s inresing soil orgni mtter, will enhne the vilility of plnt nutrients through minerliztion of orgni mtter nd improved root development (Cho, 2016). In this frming pproh, mrketle fruits re hrvested nd remining plnt residues re left in the field or re onverted into liquid fertilizer. Liquid fertilizers nd pestiides re produed on site, using lolly ville inputs. Diluted sewter n e used s minerl fertilizer. This preliminry report suggests the need for further evlution of urrent ppy prodution prties in the Pun Distrit of Hwii. Sientifilly designed field studies re needed to determine if lterntive nutrient soures ould e used to rete sustinle nd profitle ppy prodution system. This should inlude the nutrient omposition of inputs, osts, nd the potentil enefits tht growers my reeive if they trnsition to orgni prodution. Furthermore, lterntives to the urrent lnd use prties, suh s over ropping, psture rottion with livestok, nd nturl frming or orgni prodution methods sed on lolly soured low-ost inputs, should e evluted for their potentil ontriution to more sustinle nd profitle ppy prodution system in Hwii. P. Agri. Nt. Resour.

10 10 Preliminry Report on the Minerl Composition of Ppy Soil nd Plnt Tissue in Pun, Hwii Under Different Lnd Use Prties Dislimer Mention of trdemrk, proprietry produt, or vendor does not onstitute gurntee or wrrnty of the produt y the University of Hwii t Hilo nd does not imply its pprovl to the exlusion of other produts or vendors tht lso my e suitle. Aknowledgements The uthors would like to thnk Mr. Eri Weinert, generl mnger of Clvo Growers In. for shring his onerns out the urrent stte of ppy prodution in Hwii nd inititing the proess to ddress these onerns in sustinle mnner. We would lso like to thnk Mr. Rndy Ako, griulturl mnger t W.H. Shipmn Limited for his oopertion in smple olletion. Funding ws provided y the USDA-PBARC Integrted Cropping System Projet. Agreement No S/greement S under Dr. Brue Mthews, Interim Den, CAFNRM, UH Hilo. Referenes Awd, M. nd R. H. Suehis Critil nitrogen level in petioles of ppy. Honolulu, Hwii: Hwii Agriulturl Experiment Sttion, University of Hwii. Cho, Y JADAM Orgni Frming. The wy to Ultr-Low-Cost griulture. JADAM, Yuseonggu, Dejeon, Repuli of Kore. Evns, E.A., F.H. Bllen, nd J.H. Crne An Overview of US Ppy Prodution, Trde, nd Consumption. Hte, M., nd N.W. Osorio Arusulr myorrhizs: produing nd pplying rusulr myorrhizl inoulum. CTAHR, Univ. of Hwii, Honolulu. 47 pp. Mnshrdt, R.M The Ppy in Hwi i. Hortiulturl Siene 47 (10): Mthews, B.W., nd R.S. Senok Sustinle soil mngement in the high rinfll res of Hwi i Islnd nd the use of some onventionl nd lterntive fertilizers. J. Hwiin Pifi Agri. 9:7-32. Mtson, P.A., W.J. Prton, A.G. Power, nd M.J. Swift Agriulturl Intensifition nd Eosystem Properties. Siene (New York, N.Y.). 277(5325): Mills, H. nd J. Jones Jr Plnt nlysis hndook II, A prtil smpling, preprtion, nlysis nd interprettion guide. Athens, GA, MiroMro Pulishing. Miysk, S.C., M. Hte, J.B. Fridy, nd E.V. Johnson Mnul on Arusulr Myorrhizl Fungus Prodution nd inoultion tehniques. Soil nd Crop Mngement SCM-5. College of Tropil Agriulture & Humn Resoures, University of Hwii t Mno. Nishin M., F. Zee, R. Eesu et l Ppy prodution in Hwii. Honolulu (HI): University of Hwii. 8 p. (Fruits nd Nuts; FN-3). Osher, L., J. Mtson, nd P. Amundson Effet of Lnd Use Chnge on Soil Cron in Hwii. Biogeohemistry 65(2): Qiu, Y. M.S. Nishin, nd R.E. Pull Ppy Fruit Growth, Clium Uptke, nd Fruit Ripening. Journl of the Amerin Soiety for Hortiulturl Siene 120(2): SAS Institute In SAS Softwre, SAS Studio 3.1. Cry, NC, USA Sukrno, N., S. Smith, nd E. Sott. (1993). The effet of fungiides on vesiulr rusulr myorrhizl symiosis. New Phytologist, 125(1): Tmimi Y.N., J.A. Silv, R.S. Yost, nd N.V. Hue Adequte nutrient levels in soils nd plnts in Hwii. Honolulu (HI): University of Hwii. 2 p. (Agronomy nd Soils; AS-3). Uhid R Reommended plnt tissue nutrient levels for some vegetle, fruit, nd ornmentl folige nd flowering plnts in Hwii. In: Plnt nutrient mngement in Hwii's soils: pprohes for tropil nd sutropil griulture. J.A. Silv nd R. Uhid, eds. College of Tropil Agriulture & Humn Resoures, University of Hwii t Mno. Uhid R. nd N.V. Hue Soil Aidity nd Liming. In: Plnt nutrient mngement in Hwii's soils: pprohes for tropil nd sutropil griulture. J.A. Silv nd R. Uhid, eds. College of Tropil Agriulture & Humn Resoures, University of Hwii t Mno. USDA-ERS Fruit nd Tree Nut Yerook 2015: Ppy (B-23). United Sttes Deprtment of Agriulture, Eonomi Reserh Servie, Wshington, D.C. 22/2015/FruitndTreeNutYerook2015.pdf. P. Agri. Nt. Resour.