Ppm NAA Research Articles

ROOTING SEMI-HARDWOOD STEM CUTTINGS OF Ficus deltoidea Jack PLANT

A set of pot experiments was conducted under plastic house conditions at the nursery of Hort. Res. Inst., Giza, Egypt during 2007 and 2008 seasons to detect the response of 10-12 cm long semi-hardwood stem cuttings of Ficus deltoidea Jack taken at the last week of February to a basal quick-dip for only 10 seconds in the hydro-alcoholic solutions of 1-Naphthaleneacetic acid (NAA) at the rates of 0, 2000, 4000 and 6000 ppm, and 2,4-Dichlorophenoxyacetic acid (2,4-D) at 0, 200, 400 and 600 ppm levels, with benzyladenine (BA) at the concentration of 100 ppm or without (0.0 ppm). The obtained results indicated that all treatments significantly increased rooting (%), No. roots/ cutting, root length (cm) and the percent of rooting efficiency index (REI %). Transplant height (cm), No. branches and leaves/transplant, as well as leaves, stem and roots fresh and dry weights (g) were also improved in response to dipping in solutions of the various growth regulators used in this study. Total carbohydrates content (mg/g dry weight) was greatly increased in the leaves of treated transplants, while total indoles and total phenols were significantly decreased with the notice that the rate of decrement in total phenols content was higher than that induced in total indoles content. In general, NAA treatments gave better results than 2,4-D ones, whereas participation of BA (100 ppm) with the aforementioned auxins resulted additional improvements in some parameters unlike some others. However, the prevalence in most of the previous measurements was for the combined treatment between 6000 ppm NAA and 100 ppm BA. Hence, it is recommended to get the best rooting with high quality of the new formed vegetative growth.

Induksi dan Multiplikasi Tunas Jarak Pagar (Jatropha curcas L.) Secara In Vitro

The conventional propagation of physic nut ( Jatropha curcas ) is difficult, because it requires a high number of mother plant, which is very limited. In vitro culture is an alternative technique to conventional one to solve the problem. An experiment was done to obtain the best in vitro culture media for shoot induction and multiplication. This research was separated into two steps, (1) in vitro induction of explant growth, and (2) in vitro shoot multiplication. Results showed that medium of WPM + 2.0 ppm BAP induced shoot and leaf better than the control. The highest number of leaf axillary's multiplication was obtained from the medium WPM + 2.0 ppm BAP + 0.1 ppm NAA. Various medium formulations for the induction and multiplication of shoots resulted in highly leaf fall. The use of DKW + 2.0 ppm BAP + 0.4 ppm TDZ + 3.0 ppm AgNO 3 medium has effectively induced shoot multiplication and reduction of dehydrated leaf. Meanwhile, the used of DKW medium supplemented with 5 ppm kinetin resulted in the best shoot elongation. Key words : Induction, in vitro, Jatropha curcas , shoot, multiplication

Winter Stem Cutting Propagation of ‘Dwarf Burford’ Holly without Use of a Conventional Auxin Treatment

‘Dwarf Burford’ holly (Ilex cornuta ‘Dwarf Burford’) is a significant nursery crop and is widely used in landscapes in U.S. Department of Agriculture hardiness zones 7 to 9. Stem cuttings can be rooted at multiple times during the year, provided cutting wood is sufficiently mature, with auxin treatments traditionally used to encourage rooting. This study was conducted to determine if auxin treatment could be eliminated, thus reducing labor and chemical requirements in the cutting propagation process. In three experiments, terminal stem cuttings of ‘Dwarf Burford’ holly were taken in winter, prepared with and without use of a basal quick-dip in an auxin solution, and rooted in a warm, high-humidity environment. Rooting percentages for nontreated cuttings and cuttings treated with 2500 ppm indole-3-butyric acid (IBA) + 1250 ppm 1-naphthaleneacetic acid (NAA) were similar, while treatment of cuttings with 5000 ppm IBA + 2500 ppm NAA resulted in a decrease in rooting percentage. The number of primary roots and total root length were similar among the three treatments, except in one experiment where total root length was greater with auxin-treated cuttings than with nontreated cuttings. Initial shoot growth responses were variable among the three experiments. The treatment of cuttings with auxin was not required for successful rooting and can be eliminated from the process for winter stem cutting propagation of ‘Dwarf Burford’ holly.

Fruit Bio-thinning by Plant Growth Promoting Bacteria (PGPB) in Apple cvs. Golden Delicious and Braeburn

ABSTRACT During 2006 and 2007, fruit thinning effects of three plant growth promoting rhizobacteria (PGPB) strains (Bacillus OSU-142, Microbacterium R23 and Bacillus T7) and NAA (10 and 20 ppm) were tested in apple cvs. Golden Delicious and Braeburn in terms of fruit setting, yield, fruit weight, fruit firmness, total soluble solid (TSS), titratable acidity and shoot length in the province of Konya, Turkey. Bacterial strains were sprayed at 7, 14 and 21 days after full bloom, and NAA was sprayed at 21 days after full bloom. The results showed that NAA and bacterial treatments decreased fruit setting and number of fruit per tree at various ratios in both cultivars. The lowest fruit setting cvs. Golden Delicious and Braeburn were obtained from 20 ppm NAA treatment in both years. Among the bacterial treatments R23 (24.1% in 2006 and 39.1% in 2007) in Golden Delicious and R23 (11.6% in 2006) and T7 (17.3% in 2007) in Braeburn gave the lowest fruit setting ratio while fruit setting ratio in Golden Delicious and Braeburn were 36.7 and 46.2% (2006) and 12.8 and 28.2% (2007) in the control, respectively. The highest fruit number was found from the control in both cultivars and years. Fruit yield was significantly decreased in Golden Delicious by NAA treatments but not affected in Braeburn by thinning. The highest yield was found from the control in cvs. Golden Delicious and Braeburn in both years. However, fruit weight was significantly increased by NAA and bacterial treatments. While the lowest fruit weight was in the control in both cultivars and years, the highest fruit weight was in R23 in Golden Delicious (164.6 g in 2006) and T7 (138.7 g in 2006) and OSU-142 (173.5 g in 2007) treatments in Braeburn. Treatments of R23 and T7 significantly increased fruit firmness in Golden Delicious and Braeburn in both years, respectively compared with the control. NAA and bacterial applications also significantly increased TSS in Braeburn but not Golden Delicious. The results of this study suggest that Bacillus OSU-142, Microbacterium R23 and Bacillus T7 have the potential to be used as fruit thinning agents under organic and sustainable growing conditions on apple.

Micropropagation and Comparative Study of Chemical Components of Essential Oils of in-vitro and in-vivo Grown Mentha spicata L.

Axenic shoot culture of Mentha spicata L. was established from young shoots of the plant naturally growing in the field. Large number of multiple shoots were observed on MS media supplemented with NAA (0.5ppm) and BAP (1ppm) within eight weeks of culture. Extensive root formation was observed on MS medium supplemented with 1 ppm NAA. Essential oils from both in vitro and in vivo samples showed l- carvone as a major constituent, however, the in vitro samples showed higher concentration of menthol than in vivo samples. <i>Nepal Journal of Science and Technology</i> Vol. 7, 2006

Metabolic changes during adventitious root primordium development in Tectona grandis Linn. f. (teak) cuttings as affected by age of donor plants and auxin (IBA and NAA) treatment

Aging of the donor tree decreased adventitious root formation in shoot cuttings of Tectona grandis Linn. f. (teak). Exogenous application of auxins, i.e., a-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) has a significant positive effect on the percentage of rooting. The maximum percent rooting was obtained with 4,000 ppm IBA as compared to other treatment. Significant increase in root number was recorded in shoot cuttings treated with 4,000 ppm NAA. The overall rooting response was better in the treatment with IBA rather than with NAA. Further periodic samples (0, 10, 20, and 30 days) were taken to assess the total soluble sugar, starch, protein, and peroxidase (PER) activity in the rooting zone of shoot cuttings of teak during adventitious root formation. Application NAA and IBA to shoot cuttings resulted in an increase in the level of total soluble sugar, starch, protein, and PER-activity in the rooting zone. The stored carbohydrates were utilized during adventitious root formation. Hence, total soluble sugar and starch contents of cuttings, irrespective of age of donor plants, decreased with the passage of time in cuttings planted for rooting. Significant fluctuations were observed in the protein content of cuttings during the time of root induction. There was an increase in the protein content with the passage of time from the day of planting up to its 20th day, followed by a sharp decline in the protein content of cuttings at the 30th day of planting, irrespective of the age of donor plants or the treatment of cuttings with auxins. Irrespective of donor plant age, PER-activity in the cuttings increased from the day of their planting for rooting up to the 20th day, and then declined at its 30th day of planting. It was interesting to note that PER-activity remained higher at all stages in the cuttings of 2-month-old seedlings which rooted profusely as compared to the cuttings of 15- and 30-year-old donor plants those rooted poorly. This study

Promotion of Flowering in Apple with NAA and Ethrel

Experiments were carried out in the southeastern United States between 1998 and 2006 to evaluate the potential for applications of NAA, Ethrel, or both, in the on-year of a biennial bearing cycle to increase return bloom in apple. Four bi-weekly applications of 5 ppm NAA beginning in mid June (summer NAA) increased return bloom, measured as the percentage of floral spurs in the year after treatment. The level of return bloom on trees receiving a summer NAA program was more than 2-fold higher than on untreated control trees, averaged across seven different experiments. Four applications of 5 ppm NAA at weekly intervals leading up to harvest (August/September) increased return bloom also. Combining 150 ppm Ethrel with summer NAA sprays resulted in an additive effect on return bloom compared to NAA or Ethrel alone. The effect of flower cluster density on return bloom the following year was more negative on control trees than it was on trees sprayed with Ethrel in the previous year. Treatment effects on fruit maturity at harvest were generally neutral, although flesh firmness was reduced in some experiments. NAA or Ethrel sprays in the on-year of a biennial bearing cycle may provide a strategy for achieving more consistent flowering and cropping in apple.

Effect of Plant Growth Regulators on growth and Yield of Brinjal at Khajura, Banke

A field study was conduced in split-plot design with three replications to assess the effect of plant growth regulators (PGRs) on morphological characters and yield of brinjal cvs. Pusa Purple Long (PPL) and Pusa Purple Cluster (PPC) as main plot factor at Khajura, Banke district during summer-rainy season of 2004. The sub-plot treatments composed of fresh water (control), 40 ppm NAA, 10 ppm GA3, 2 ppm 2,4-D, 300 ppm ethephon, 30 ppm BAP and 5 ppm triacontanol. The first spray was at flowering stage and the others at 20 days interval. The PGRs had no significant effect on plant height and stem diameter at the end of crop period and days to 100% plant flowering whereas the cultivars differed significantly. The PPL was earlier to 100% plant flowering, which took 33 days after transplanting. The treatments had no significant influence in fruit number per plant and fruit yield. The interaction effect showed that the. PPL did not produced statistically different fruit number per plant with respect to growth regulators, while it had significantly higher fruit yield (17.76 t/ha) at 40 ppm NAA than that at 10 ppm GA3 and 30 ppm BAP. The PPC produced significantly higher fruit number per plant and higher fruit yield (t/ha) at 30 ppm BAP than all other treatments except 5ppm triacontanol. 
 
 Key words: Growth regulators, cultivar, season, marketable, unmarketable, yield 
 
 J. Inst. Agric. Anim. Sci. 27:153-156 (2006)

Effect of Plant Growth Regulators on Growth, Yield and Quality of Chilli (<i>Capsicum annuum</i> L.) at Rampur, Chitwan

The present investigation was carried out in the plain areas of Chitwan to determine the promising plant growth regulators (PGR) promoting growth and yield of chilli cultivars Jwala and Suryamukhi during winter-summer season of 2003/2004. Suryamukhi ranked superior to Jwala for most of the yield attributing characters, whereas Jwala was better in vegetative characters than Suryamukhi. Among PGRs, 2,4-D at 2 ppm was better for fruit set, number of fruits per plant, fruit length, number of seeds per fruit, seed weight per fruits, 1000 seed weight and fruit yield where as NAA at 40 ppm gave the highest leaf area index (LAI). PGRs were ineffective in promoting flowering and fruiting during winter season. GA3 at 10 ppm exhibited maximum amount of ascorbic acid content. The treatments, 2 ppm 2,4-D, 5 ppm triacontanol, 40 ppm NAA and 10 ppm GA3 produced 28.75%, 25.70%, 13.61% and 2.30% higher fruit yield over control, respectively. The highest net profit and B:C ratio were recorded in case of 2 ppm 2,4-D. The use of GA3 as foliar spray was not economical. 
 
 Key words: 2,4-D, NAA, triacontanol, GA3, leaf area index, net profit, B:C ratio 
 
 J. Inst. Agric. Anim. Sci. 27:65-68 (2006)

Rooting Osha Crown Cuttings Using IBA and NAA

Osha (Ligusticum porteri) is a Rocky Mountain native frequently used as a medicinal herb. It is currently harvested largely from the wild. Studies have been under way since 2001 to find ways to propagate and produce the plant. To potentially increase rooting success of crown cuttings of osha, two different rooting hormones were used, each at two concentrations. Treatments were controls, 2500 ppm, and 5000 ppm solutions each of indole-3-butyric acid (IBA) and α-naphthalene acetic acid (NAA). Cuttings were soaked in deionized water or treatment solutions for 2 min. After soaking cuttings were stuck in sterilized sand in 725-mL2 containers, one cutting per container. Containers were placed on a mist propagation bench at 21 °C in a completely randomized design under natural light and day lengths. Data taken were days to visible root and shoot, and presence or absence of root formation after 50 days. Results indicated only one of 70 cuttings (<1%) produced a shoot. Roots formed on 14% of control cuttings, 64% in 2500 ppm IBA, 86% in 5000 ppm IBA, 36% in 2500 ppm NAA, and 14% in 5000 ppm NAA. Days to rooting ranged from 14.9 (2500 ppm IBA) to 29.0 (5000 ppm NAA). Due to considerable variation in days to rooting, and the number of cuttings that did not root, analysis of variance showed no differences among treatments. Frequency analysis indicated differences among treatments in root presence or absence. The 2500 and 5000 ppm IBA treatments showed more root formation than the controls or either NAA treatment. This indicates IBA may enhance rooting of osha crown cuttings.

Clonal Propagation of Teak (Tectona grandis) by compositive treatment of Auxin with Thaimine

A pilot study was conducted in order to evaluate efficacy and economy of large-scale production of clonal plantlets of Teak. Semi-hardwood shoot cuttings taken from vegetative multiplication garden were treated with low doses of composite auxins (IAA, IBA and NAA) in combination with thiamine. Strong synergistic interaction between thiamine and auxins was observed for adventitious rhizogenesis, as the resultant increment in adventitious rhizogenesis due to combined auxin and thiamine application was several folds greater than from the independent application of auxins and thiamine alone. Treatment of 1200/800 ppm thiamine with a combined dose of auxins (250 ppm IBA, 125 ppm IAA and 125 ppm NAA) proved to be the most effective for rooting with increment of 4.85 and 4.79 times, respectively over the control. These treatments have been recommended for production of clonal planting stock of Teak on mass scale in open non-misting conditions.

Studies on Psathyerella atroumbonata (Pegler), a Nigerian edible fungus

The effects of temperature, pH, vitamins and phytohormones on growth of Psathyerella atroumbonata (Pegler), a Nigerian edible mushroom were investigated. This fungus was able to grow at a temperature range of 15–45 °C (optimum=30 °C) and pH range of 5.0– 8.0 (optimum=6.5). Exogenous supply of vitamins significantly enhanced the growth of the fungus ( P=0.01). Similarly, biotin was found to be the most stimulatory vitamin while nicotinic acid was the least utilised. The best phytohormone that sustained good growth was 1.0 ppm NAA while 20.0 ppm 2,4-D inhibited growth of this mushroom. The relevance of these findings in relation to cultivation of P. atroumbonata in Nigeria is considered.

Steroidal saponin production in callus cultures of Solanum aculeatissimum Jacq.

Callus was induced from the epicotyl of S. aculeatissimum, and the relation between culture conditions and the production of steroidal saponins in the callus was studied. The results indicated that the callus produced the steroidal saponins aculeatiside A and B. The highest production of steroidal saponins occurred at the middle of the log phase. Optimal conditions for the production of steroidal saponins were culturing on MS basal medium supplemented with the combination of 0.05 ppm or 0.1 ppm NAA and 10 ppm BA, and fructose as a carbon source, in the dark at 25 °C. Under these optimal conditions, the callus produced 0.8% (per dry weight) steroidal saponins, or 0.32% aculeatiside A and 0.48% aculeatiside B.

270 Effects of Chemical Thinners on Yield, Fruit Size, and Fruit Quality of `Honeycrisp' Apple

Effects of chemical thinners on yield, fruit size, and fruit quality was studied in a commercial orchard in Milton, N.Y., on 6-year-old `Honeycrisp'/M.26 trees. The trees were planted at 1.8 × 3.6-m spacing with trickle irrigation and were trained to the vertical axis system. The treatments applied in a randomized complete-block design with four replications were an untreated control; carbaryl (Sevin XLR at 125 mL/100 L); NAA at 2.5 ppm, 5 ppm, or 7.5 ppm; NAA at 2.5 or 5 ppm plus carbaryl; and Accel (a.i. at 74 g·ha-1) plus carbaryl. Chemical thinners were applied to drip with an air-blast sprayer, when the largest fruit were 11.5 mm in diameter. Generally, thinning activity increased with increasing NAA concentration. The combination sprays of 5 ppm NAA plus carbaryl, and Accel plus carbaryl over-thinned `Honeycrisp'. Carbaryl alone was inconsistent. All thinning treatments increased fruit size relative to unthinned trees, with average fruit diameter exceeding 76 mm. `Honeycrisp' is a large-fruited cultivar that is easy to thin chemically at the traditional 10- to 12-mm growth stage. NAA at 2.5 or 5 ppm provided adequate thinning to produce fruit of good quality and size. If initial set is heavy and a stronger thinning response is desired, the combination of 2.5 ppm NAA plus carbaryl could be used. `Honeycrisp' appears to be very sensitive to Accel, when used in combination with Sevin XLR. Further research needed before Accel is used to thin `Honeycrisp'.

296 Chemical Thinning of `Fuji' Apple with Ethephon, NAA, MCPB-ethyl, and Carbaryl

We propose that return flowering of `Fuji' apple can be improved if sufficient flower clusters are removed during or shortly after bloom. In this study conducted at Corvallis, Ore., we evaluated two synthetic auxins, MCPB-ethyl and the Na salt of NAA, each at 0, 4, 8 and 16 ppm, as blossom cluster thinners. Each auxin treatment was applied alone or with 100 ppm ethephon as a tank mix. Six-year-old `Fuji'/M.26 trees were sprayed at full bloom of the king flowers (≈85% of whole-tree full bloom). A follow-up treatment of Sevin XLR (800 ppm carbaryl) was made at 11-mm fruit diameter to determine if carbaryl's known effectiveness as a fruitlet thinner was influenced by the bloom-time auxin or auxin + ethephon treatments. MCPB-ethyl proved ineffective as a bloom-time thinner, whereas the NAA effect on cluster removal was linear with concentration, 16 ppm NAA completely defruiting 33% of initial flower clusters. On control trees fewer than 12% of flowering clusters failed to set fruit. Ethephon alone defruited 25% of the clusters and NAA+ethephon defruited 51% of clusters. It is notable that the NAA and ethephon + NAA treatments did not reduce fruit set on the remaining clusters, resulting in considerable need for hand-thinning. Carbaryl effectively reduced total crop load by increasing the number of defruited clusters and reducing the incidence of doubles and triples. There was evidence to suggest that its effectiveness was compromised by the bloom-time NAA and/or ethephon sprays.

Nursery Rooting and Growth of Loblolly Pine Cuttings: Effects of Rooting Solution and Full-Sib Family

Abstract This research examined the effects of various rooting solutions and full-sib families on the rooting ability and subsequent growth and morphology of dormant loblolly pine stem cuttings set directly into open nursery beds. Two recommended concentrations of a commercial rooting compound (Woods Rooting Compound®), 9 and 17% (10:1 and 5:1 dilutions, respectively), and a water control in combination with four boron and four thiamine concentrations were tested. The 9% concentration contained 924 ppm indole-3-butyric acid (IBA ) + 594 ppm α-naphthaleneacetic acid (NAA) while the 17% concentration contained 1751 ppm IBA + 1122 ppm NAA. Family, rooting compound concentration, and their interaction were significant, while boron and thiamine main effects were not significant for percent rooted nor other traits assessed. Overall, 75% of cuttings treated with the water control rooted while cuttings receiving the 9 and 17% rooting compound concentrations rooted at 64 and 55%, respectively. However, the root systems of cuttings receiving the rooting compound treatments were more symmetrical, more vertically oriented and had greater dry weights than cuttings receiving the water control treatment. In addition, basal stem caliper and shoot dry weight, as well as the root:shoot ratio, were greater for cuttings receiving the rooting compound treatments. The trade-offs between rooting percent and root system morphology were addressed by investigating treatment differences in final crop yields as a percent of cuttings set. When seedling caliper standards were used as the grading criteria, no rooted cuttings were culled. Under this scenario, the water control treatment yielded the highest percent of acceptable (combined Grades 1 and 2) rooted cuttings (75%) since it also yielded the highest rooting percent. The range in yield of acceptable rooted cuttings for the five full-sib families receiving the water control treatment was 58 to 84%. When additional root system standards were imposed upon the caliper grades, the 9% rooting compound concentration yielded the highest percent of acceptable rooted cuttings (53%). The range in acceptable yields of the five full-sib families receiving the 9% rooting compound treatment when the additional root system grading standards were imposed, was 35 to 79%. A better understanding of the trade-offs between rooting percent and root system morphology as well as the effect of root system morphology on long-term growth of cuttings is needed. However, the rooted cuttings produced in this study by directly setting cuttings into open nursery beds exceeded commonly used seedling grading standards. While production costs were not addressed in this study, and significant additional development is needed, these results provide encouragement that an economical system of rooting loblolly pine cuttings in open nursery beds may be feasible. South. J. Appl. For. 23(2):108-115.

クロユリのｉｎ ｖｉｔｒｏ培養による増殖に関する研究 （第２報） 子球の肥大，出葉および発根に対する植物ホルモンの効果について

本実験はクロユリ(Fritillaria camtschatcensis Ker-Gawl.)の小球状りん片由来の子球を25℃, 1, 500lxで8週間培養した.そしてNAA, カイネチンおよび24-Epibrassinolide(EB)による子球の肥大と子球からの発根および出葉に対する効果を検討した.各植物ホルモン実験の結果, 培養8週間後の子球の肥大と発根にはEB0.01ppmが, また子球からの出葉にはカイネチン0.1ppmが効果的であった.組み合わせた植物ホルモン実験の結果, 培養8週間後の子球の生育にはNAA 1.0ppm, カイネチン0.1ppmおよびEB0.01ppmの3者の組み合わせが最も効果的であった.

Thinning and Growth Control of Apples Treated with BAS-125 10W

BAS-125 10W is a new plant growth retardant that was evaluated on `McIntosh' apples to control excessive vegetative growth. When applied at concentrations between 0 and 375 ppm, it significantly reduced terminal growth. As a result, light penetration into the tree was increased and fruit at harvest had more red color, and more were graded into the US Extra Fancy category. BAS-125 increased fruit set; thus, fruit were smaller, but firmer, at harvest. Treated fruit were firmer and had less decay following 20 weeks of regular air storage. Several different thinning strategies were employed to thin BAS-125-treated `Delicious' trees. In one experiment, the best thinning treatment was a combination spray containing 10 ppm NAA plus carbaryl at petal fall followed by 8 ppm NAA when fruit size averaged 10 mm. The best treatment in another experiment was a Wilthin application at 80% bloom followed by 8 ppm NAA plus carbaryl at petal fall. Recommendations for the successful use of BAS-125 10W in the Northeast will be discussed.

Rooting Ability of Microcuttings of Desert Almond (Amygdalus arabica Oliv.)

Three experiments were performed to establish rooting procedure of Amygdalus arabica Oliv. Two-centimeter shoots grown in vitro on MS medium supplemented with IBA at 0.01 mg/L, BA 0.2 mg /L, sucrose 30.0 g/L, and agar 6.0 g/L were used in rooting microcuttings using three experiments: 1) IAA, IBA, and NAA at concentrations of 0.5, 1.0, and 1.5 mg/L during the whole experiment with 4 days of dark period; 2) effect of dark and light conditions and IBA and NAA treatments during root induction period (4 days), then shoots were transferred onto free plant bioregulators (PBR), MS medium until end of the experiment; 3) Rooting microcuttings after quick dipping in different NAA concentrations (0.0, 250, 500 ppm) or induced for 6 days in root induction medium (MS) with 3.0 mg/L NAA, then shoots were transferred onto containers containing 200 ml of peatmoss, perlite, or peatmoss: perlite mixture (1:1, v/v). Results of the first experiment showed that best rooting was obtained with NAA, followed by IBA. In the second experiment, dark treatments improved rooting percentage and root length. NAA was superior to IBA in root number. Higher IBA and NAA (3.0 mg/L) concentrations gave the best rooting. In the third experiment, induced shoots transferred to perlite gave better root number and rooting percentage followed by peatmoss: perlite mixture. Regardless of rooting medium, insignificant differences between 250 and 500 ppm NAA in root number and rooting percentage were obtained. In the quick dip method, NAA was superior to the in vitro root induction method. The highest rooting percentage (86.7%) was obtained with perlite at either 250 or 500 ppm, replacing by that the traditional in vitro rooting and obtaining plantlets that are more ready to grow under in vivo conditions.

Somatic Chromosome Numbers of Colchicine-Treated Shinano Walnut (Juglans regia L.) and Its F1 Seedlings

Shoots of Shinano walnut cv. 'Mituru' (main cultivar in Nagano prefecture) which is said to be a hybrid between Teuchi walnut (Juglans regia var. orientis Kitamura) and the Persian walnut (J. regia L.), was treated in 1970 with 0.4% colchicine solution containing 1 ppm NAA. Scions from the colchicine-treated 'Mituru' trees, known as 'Col-Mituru', were grafted on several rootstocks and grown to maturity. 'Col-Mituru' trees were then selfand open-pollinated. Shoot tips from 'Mituru', 'Col-Mituru', and F1 seedlings were reacted with Feulgen's reagent and silver iodide (Ag-I) to stain the chromosomes; their chromosome were then counted. 1. In 'Mituru' with 32 chromosomes, 62 nuclear plates were observed in the shoot tips, an amount which is twice the normal diploid number in J. regia and 'Mituru'. 2. Chromosome number of 'Col-Mituru', and its grafted propagagules, 84-1, 84-2, and 84-3, is 64 in 90 out of 95 nuclear plates counted. This is four times the basic haploid number; thus, the trees are tetraploids.3. The chromosome numbers in 7 F1 seedlings obtained from open-pollinated 'Mituru' is 32 in 192 out of 193 cells counted; hence, they are diploids. 4. Twenty seedlings obtained from 'Col-Mituru' (4x) × 'Mituru' (2x) and 'Housho' (2x) have 48 chromosomes. Likewise, the 14 open-pollinated seedlings of 'Col-Mituru' had 48 chromosomes in 408 out of 410 nuclear plates. They are triploids. 5. In two seedlings obtained in 1983 from self-pollination of 'Col-Mituru', one had 64 and the other 48 chromosomes; they are tetraploid and triploid, respectively. The pollen for the triploid probably came from a diploid source. Of 10 self-pollinated seedlings derived in 1984. all had 64 chromosomes; they are, therefore, believed to be tetraploids.