Simpulan
Penelitian adaptasi bibit tanaman Eucalyptus pellita dari 10 kelompok
sumber benih terhadap cekaman kekeringan, dapat diambil beberapa simpulan. Adapun simpulan yang dapat disimpulkan dari penelitian ini adalah :
1. Secara umum bibit tanaman E. pellita kurang tahan terhadap kondisi
cekaman kekeringan yang terlihat dari penurunan pertumbuhan lebih dari 50% pada semua kondisi cekaman kekeringan, namun kelompok sumber benih KBS Site II dan KBK Perawang dan APB Bupul-Muting menunjukkan pertumbuhan lebih baik dibandingkan kelompok sumber benih lainnya pada kondisi cekaman kekeringan 50% dan 25%.
2. Mikoriza arbuskula membantu meningkatan ketahanan bibit E. pellita
terhadap cekaman kekeringan sampai pada taraf cekaman kekeringan 75% denga n meningkatkan penyerapan air tanah, kelompok sumber benih yang peningkatan ketahanannya tinggi dengan adanya mikoriza arbuskula berasal dari KBK Perawang dan KBS Site I.
3. Mekanisme adaptasi bibit tanaman E. pellita terhadap cekaman kekeringan
dengan meningkatkan kadar prolina daun dan juga menjaga status air jaringan yaitu dengan perbaikan sistem perakaran tanaman dan penebalan helaian daun.
Saran
Dalam pengembangan tanaman E. pellita sebagai jenis tanaman dalam
rehabilitasi lahan dan atau hutan tanaman pada lahan kering, sebaiknya menggunakan benih yang berasal dari KBS Site II, KBK Perawang dan APB Bupul-Muting, namun bila menggunakan aplikasi mikoriza arbuskula, rekomendasi benih yang dapat digunakan berasal dari KBK Perawang dan KBS Site I.
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Lampiran 1 Tabel hasil analisis anova pada variable pertumbuhan tinggi dan diameter.
Tests of Between-Subjects Effects
Dependent Variable: Pertumbuhan tinggi
Source
Type III Sum of
Squares df Mean Square F Significance Model 485327,234(a) 80 6066,590 187,936 ,000 MRIZA 303,979 1 303,979 9,417 ,002 AIR 105138,799 3 35046,266 1085,692 ,000 ASAL 1185,773 9 131,753 4,082 ,000 MRIZA * AIR 698,334 3 232,778 7,211 ,000 MRIZA * ASAL 1183,071 9 131,452 4,072 ,000 AIR * ASAL 1992,745 27 73,805 2,286 ,000 MRIZA * AIR * ASAL 2181,436 27 80,794 2,503 ,000
Error 10329,636 320 32,280
Total 495656,870 400
a R Squared = ,979 (Adjusted R Squared = ,974)
Tests of Between-Subjects Effects
Dependent Variable: Pertumbuhan diameter
Source
Type III Sum of
Squares df Mean Square F Significance Model 469,612(a) 80 5,870 138,724 ,000 MRIZA ,266 1 ,266 6,292 ,013 AIR 86,528 3 28,843 681,617 ,000 ASAL 1,606 9 ,178 4,217 ,000 MRIZA * AIR ,872 3 ,291 6,866 ,000 MRIZA * ASAL 1,028 9 ,114 2,698 ,005 AIR * ASAL 1,253 27 ,046 1,097 ,341
MRIZA * AIR * ASAL 1,427 27 ,053 1,249 ,187
Error 13,541 320 ,042
Total 483,152 400
Lampiran 2 Tabel hasil analisis anova pada variable biomasa total dan nisbah tajuk akar.
Tests of Between-Subjects Effects
Dependent Variable: Biomassa total
Source
Type III Sum of
Squares df Mean Square F Significance Model 950,285(a) 80 11,879 60,918 ,000 MRIZA 3,082 1 3,082 15,805 ,000 AIR 383,190 3 127,730 655,054 ,000 ASAL 4,525 9 ,503 2,578 ,007 MRIZA * AIR 4,260 3 1,420 7,283 ,000 MRIZA * ASAL 5,075 9 ,564 2,892 ,003 AIR * ASAL 8,880 27 ,329 1,687 ,020
MRIZA * AIR * ASAL 9,402 27 ,348 1,786 ,011
Error 62,397 320 ,195
Total 1012,682 400
a R Squared = ,938 (Adjusted R Squared = ,923)
Tests of Between-Subjects Effects
Dependent Variable: Top-root ratio
Source
Type III Sum
of Squares df Mean Square F Significance Model 3266,135(a) 80 40,827 41,291 ,000 MRIZA 11,139 1 11,139 11,265 ,001 AIR 9,540 3 3,180 3,216 ,023 ASAL 21,722 9 2,414 2,441 ,011 MRIZA * AIR 9,110 3 3,037 3,071 ,028 MRIZA * ASAL 14,856 9 1,651 1,669 ,095 AIR * ASAL 40,422 27 1,497 1,514 ,052 MRIZA * AIR * ASAL 27,881 27 1,033 1,044 ,408
Error 316,405 320 ,989
Total 3582,541 400
55
Lampiran 3 Tabel hasil analisis anova pada variable kadar air relatif daun dan berat daun spesifik.
Tests of Between-Subjects Effects
Dependent Variable: Kadar Air Relatif Daun
Source
Type III Sum of
Squares df Mean Square F Significance Model 3110452,096(a) 80 38880,651 3867,355 ,000 MRIZA 38,069 1 38,069 3,787 ,053 AIR 4615,897 3 1538,632 153,044 ,000 ASAL 1145,374 9 127,264 12,659 ,000 MRIZA * AIR 1097,713 3 365,904 36,396 ,000 MRIZA * ASAL 431,585 9 47,954 4,770 ,000 AIR * ASAL 2051,059 27 75,965 7,556 ,000 MRIZA * AIR * ASAL 1793,132 27 66,412 6,606 ,000
Error 3217,137 320 10,054
Total 3113669,233 400
a R Squared = ,999 (Adjusted R Squared = ,999)
Tests of Between-Subjects Effects
Dependent Variable: Berat Daun Spesifik
Source
Type III Sum
of Squares df Mean Square F Significance Model 3339,528(a) 80 41,744 278,557 ,000 MRIZA 5,966 1 15,966 9,810 ,053 AIR 42,537 3 14,179 94,616 ,000 ASAL 10,805 9 11,201 8,011 ,051 MRIZA * AIR 6,070 3 2,023 13,501 ,000 MRIZA * ASAL 9,047 9 1,005 6,708 ,000 AIR * ASAL 18,194 27 ,674 4,497 ,000
MRIZA * AIR * ASAL 10,836 27 ,401 2,678 ,000
Error 47,955 320 ,150
Total 3387,482 400
Lampiran 4 Tabel hasil analisis anova pada variable kadar prolina daun dan derajat infeksi akar.
Tests of Between-Subjects Effects
Dependent Variable: Kadar prolina daun
Source
Type III Sum
of Squares df Mean Square F Significance Model 549,370(a) 80 6,867 2955,719 ,000 MIKO 8,081 1 8,081 3478,339 ,000 AIR 34,560 3 11,520 4958,426 ,000 ASAL 2,393 9 ,266 114,442 ,000 MIKO * AIR ,224 3 ,075 32,120 ,000 MIKO * ASAL 3,511 9 ,390 167,913 ,000 AIR * ASAL 4,097 27 ,152 65,304 ,000
MIKO * AIR * ASAL 7,385 27 ,274 117,728 ,000
Error ,372 160 ,002
Total 549,741 240
a R Squared = ,999 (Adjusted R Squared = ,999)
Tests of Between-Subjects Effects
Dependent Variable: derajat infeksi akar
Source
Type III Sum
of Squares df Mean Square F Significance Model 29700,000(a) 80 371,250 9,281 ,000 MIKO 7593,750 1 7593,750 189,844 ,000 AIR 2921,250 3 973,750 24,344 ,000 ASAL 783,750 9 87,083 2,177 ,026 MIKO * AIR 641,250 3 213,750 5,344 ,002 MIKO * ASAL 543,750 9 60,417 1,510 ,148 AIR * ASAL 1391,250 27 51,528 1,288 ,170 MIKO * AIR * ASAL 1871,250 27 69,306 1,733 ,020
Error 6400,000 160 40,000
Total 36100,000 240
57
Lampiran 5 Hasil analisis sifat fisika dan kimia media tanam
Jenis analisis Nilai Keterangan
Tekstur Pasir (%) 6.10 Liat Debu (%) 20.79 Liat (%) 73.11 Kadar air pF 2.54 (%) 44.21 Kapasitas lapang
pF 4.20 (%) 27.46 Titik layu permanent
pH (1 : 1)
pH H2O 4.50 Asam
pH HCl 3.70 Asam
C-organik (Walkley & Black) % 2.64 Tinggi
N-total (Kjeldhal) % 0.24 Sedang
C/N ratio 11 Sedang
P (Bray I) ppm 8.6 Sangat rendah
P (HCl 25%) ppm 206.6 Sangat tinggi Basa-basa Ca (me/100 gram) 0.47 Mg (me/100 gram) 0.28 K (me/100 gram) 0.17 Na (me/100 gram) 0.13 KTK (me/100 gram) 23.38 KB (%) 4.49
Al-dd (me/100 gram) 1132.00
H-dd (me/100 gram) 0.51
Fe (me/100 gram) 4.08
Cu (me/100 gram) 0.08
Zn (me/100 gram) 0.68
Mn (me/100 gram) 7.56
Lampiran 6 Hasil perhitungan berat tanah yang harus dipertahankan pada masing- masing perlakuan cekaman kekeringan.
Kadar air kapasitas lapang (pF 2.54) = 44,21%
Kadar air layu permanen (pF 4.20) = 27,46%
Air tersedia tanaman ( pF 2.54 – pF 4.20 ) = 16,75%
Berat tanah kering mutlak (1000 gr) = 745,63 gr
Perhitungan kadar air perlakuan dan berat tanah yang dipertahankan adalah
Tingkat cekaman air
Kadar air tana h
Berat tanah perlakuan
100% air tersedia 44,21% 1075,27 gr ≈ 1075 gr
75% air tersedia 40,02% 1044,03 gr ≈ 1045 gr
50% air tersedia 35,83% 1012,79 gr ≈ 1015 gr