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dilaksanakan pada bulan Mei sampai denn Oktober 2012. Tiga faktor perlakuan yang dikombinasikan secara faktorial adalah dosis spora endomikoriza jenis Glomus sp 0; 25; 50 dan 75 butir; kompos
organik 0, 10 dan 20 gr dan pupuk pupuk N non organik 0 dan 5 gr, sehingga terdapat 24 kombinasi perlakuan. Perlakuan diuji dengan rancangan Acak Kelompok RAK dengan tiga ulangan.
Pemanfaatan pupuk hayati Glomus sp berdasarkan hasil penelitian sebelumnya Meti-unpublished data. Bibit tanaman mente diperoleh dari penanaman biji gelondongan mente yang diperoleh dari
petani mente di kawasan Kecamatan Kubu Kabupaten Karangasem.
Hasil analisa menunjukkan bahwa perlakuan kombinasi dosis spora endomikoriza 75 butir, pupuk organik 20 grdan pupuk N 0 gr memberikan pengaruh paling baik terhadap pertumbuhan bibit
mente jumlah daun dan tinggi bibit. Hasil ini penelitian juga menunjukkan bahwa penambahan pupuk hayati endomikriza tanpa pupuk organik dan N lebih baik dibandingkan dengan perlakuan tanpa
spora endomikoriza. Hasil penelitian ini menunjukkan bahwa penambahan pupuk hayati endomikroiza berpengaruh positif terhadap pertumbuhan bibit mente. Pupuk hayati endomikoriza berpengaruh secara
sinergis dengan pupuk organik namun tidak dengan pupuk non organikN.
1. Introduction
Vesicular Arbuscular Mycorrhizal VAM fungi are beneicial microorganisms that form symbiotic association with the ine roots of vascular plants and can be utilized as bio-fertilizers
supporting the plant growth because the mycorrhizal fungi play an important role in improving plant growth, nutrient uptake especially phosphorous Smith Read, 1997 ; Brundrett et al., 2008 and
provide stress tolerance and disease resistance to plants Smith et al., 2010. Efforts are being made to improve the quality of seedlings of forest trees under nursery conditions through inoculation
of suitable mycorrhizal strain alone or combined with other organic and an-organic fertilizer may improve the growth of seedlings Gill et al. 2002
Most host plants of non-arbuscular mycorrhizal fungi do not establish functional vesicular arbuscular mycorrhizal VAM symbiosis in nature Giovannetti and Sbrana 1998. Among the
known ectomycorrhizal hosts, Eucalyptus is an exception as it also forms vesicular arbuscular mycorrhiza Lapeyrie and Chilvers 1985. The present investigation analyses the effect of Glomus
sp spores number mixed with organic and an-organic fertilizer were observed on the growth of Anacardium occidentale L seedlings.
2. Materials And Methods
The spores of VAM fungi Glomus sp were isolated from the rhizosphere of Anacardium occidentale L plants and mass produced on maize Zea mays. Seedlings of Anacardium occidentale
L were procured from Divisional Forest Nursery of Bali Province.
Inoculation of Seedlings
One seedling of Anacardium occidentale L was grown in pots 30×30 cm in a sand soil mixture 1000:1000 g. Spores mycorrhizal Glomus sp i.e. 25, 50 and 75 of spores were added along
with infected roots. Observations were recorded after 15, 30, 45 and 60 days on seedlings shoot length increase in height, shoot weight and root weight. Percentage mycorrhizal root colonization,
mycorrhizal VAM spore number and phosphorous content of seedlings were studied. Three replicates of each treatment were taken.
Quantiication of VAM Spores, Root Colonization and Phosphorus Content
Percentage mycorrhizal root colonization was studied according to Kormanik dan Mc.Graw 1982 The VAM spore quantiication was also determined according to Gerdemann and Nicolson 1963.
Phosphorous content was determined by vanadomolybdate phosphoric yellow colour method Jackson 1958.
3. Results And Discussion
Result on the inoculation of Glomus sp to the cashew nut seedlings A. occidentale L. after 60 days’ growth showed that the seedling grew better compared than in the control Table 1.
The response to different treatments was in following order: 75 spores of Glomus 50 spores of Glomus 25 spores of Glomus control
Table 1. Growth of Cashew-nut seedlings to inoculation of spores VAM 60 days. __________________________________________________________________________________
__ Treatment Plant-height cm Root-lengthcm Dry shoot wtg Dry root wtg
colonization P content ppm __________________________________________________________________________________
_____________________ Control 15.0±2.82 7.0±0.70 6.95±0.31 6.05±0.45
25±3.53 0.34 25 spores 27.5±7.75 15.5±0.35 9.19±0.81 6.40±0.14
66.6±2.07 0.36 50 spores 28.5±6.01 21.0±2.82 10.8±1.22 6.85±0.17
69.6±1.34 0.42 75 spores 31.3±6.22 16.0±4.25 7.16±0.87 6.05±0.45 76
65±2.6 0.52 __________________________________________________________________________________
__ Mean of ive replicates each, ± Standard error.
The mycorrhizal root colonization in 75 spores of Glomus treatment 76.65 was higher
than the other treatments and control. On the 60 days experiment, the maximum mycorrhizal root colonization seedling height were obtained in 75 spores of Glomus , followed by 50 spores, 25
spores and the lowest was the control non-spores. Meanwhile there is an interesting trend of root length, dry shoot-roots in which the 50 spores of Glomus was highest compared than two other
treatment and control. This is indicated that the 50 spores of VAM inoculation on the cashew seedlings can increase shoot and root development and able to elongate the root system. Furthermore,
Satter et al
2005 studied the inluence of arbuscular mycorrhiza and phosphate rock on uptake of major nutrients by Acacia mangium seedlings on degraded soil. They found that use of nutrient
absorbed by seedling was more eficient in the AM-inoculated seedlings compared than that in uninoculated seedlings. Bhattacharya et al. 2000 investigated that seedling response to phosphate
addition and inoculation with arbuscular mycorrhizas and after 12 weeks, the biomass and P uptake of the mycorrhizal A.acuminata were greater than those of the non-mycorrhizal plants across all P
treatments. A relative low growth as observed in Vitex negundo
may be due to host speciicity or the root exudates which produces phyto-toxic substances. Differences among hosts were observed in
the amount of hyphae, arbuscules, and vesicles produced by the fungi, which could be attributed to growth and development characteristics among hosts and VAM fungi Kramnik et al, 2007.
The seedlings inoculated with all VAM fungi had increased phosphorous content of shoot and root over that in the control. The increased rate of P uptake and inlow in roots is regarded as the
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major contribution of VAM infection Gautam Shrestha, 2009 ; Kumar et al., 2002. The VAM colonization increased initially up to 45 days but decreased thereafter. The positive mycorrhizal
response at early seedling stage, may be due to the increase in root development. Bhattacharya et al. 2000, working on the arbuscular mycorrhizal dependence of Eucalyptus
tereticornis, found both negative and positive response of VAM fungi inoculation and concluded that E. tereticornis may not be an arbuscular mycorrhizadependent plant at early developmental
stage, although it is infected by arbuscular mycorrhizal fungi freely, improving its phosphorus acquisition eficiency in low phosphorus soil. Inluence of VAM fungi Glomus invermaium and
sheathing ECM ectomycorrhiza Descolea maculata on early growth of Eucalyptus globulus have been reported by De Olieviera et al. 1999a,b. Earlier studies by Kumar et al. 2002 and
Hazarika et al. 1999 also found Glomus mosseae inoculation to have maximum effect on the growth of chickpea plants. Rajeshwari et al. 2001 also reported that seedling growth and vigor of
casuarinas Casuarina equisetifolia raised in polybags was greater after inoculating nursery soil mixture with cultures of Glomus fasciculatum, Glomus mosseae and Glomus etunicatum,and that
Glomus fasciculatum
was more eficient. The production of large number of VAM fungi in soil-based innoculla could be attributed to
rapid sprouting from extracellular and intracellular hyphae in the soil and root inoculum. The root colonization by mycorrhiza was directly related to nutrient uptake by plants. The plants with highest
mycorrhizal root colonization had larger number of mycorrhizal spores in soil. Dodd and Thompson 1994 also observed the similar results while using the soil-based VAM inoculum. Shoot length
and fresh weight were more in 75 spores of Glomus sp-treated A. occidentale seedlings. According to Rani et al. 1999 recorder greater height and fresh weight in plant species treated Glomus sp, it
is likely that Glomus species produce growth hormones which result in better growth of the shoots Rani et al. 1999. Thus, VAM fungi of Glomus sp have a potential for utilisation to produce high
quality seedlings of A. occidentale ensuring better survival and improved growth in the nurseries.
4. Conclussion
