Daughter Bulbs Research Articles

Application of silk waste to planting of bulbous plants in construction byproduct.

The fertilizer efficiency of silk waste for planting of bulbous plants in construction byproduct as a planting ground were examined and compared with two commercial controlled release fertilizers, isobutylidene diurea (IBDU) and polyolefin-coated fertilizer. Silk waste mainly consists of silk proteins, which has high N content and is decomposed slowly in soil. Five species of bulbous plant, Narcissus tazetta var. chinensis, Lycoris albiflora, Allium chinense, Muscari armeniacum and Oxalis variabilis, were planted with each of the three fertilizers. No maintenance was carried out, except for weeding once during the experimental period. The silk waste was decomposed continuously for about 400 days, which indicated that the silk waste had fertilizer efficiency for not less than 400 days under the conditions used in this study. In the second growing season after planting, all plants grown with the silk waste or IBDU were larger than those grown without any fertilizers, except for 0. variabilis, which was hardly viable until the second season. In the case of A. chinense and M. armeniacum, no or little effects of fertilizer were seen on growth with polyolefin-coated fertilizer. Regardless of the type of fertilizer or the degree of plant growth, the ratios of green coverage, determined by image analysis, were equally increased relative to those without fertilizer, except for A. chinense and M. armeniacum with polyolefin-coated fertilizer. N. tazetta var. chinensis with IBDU had many thin leaves of daughter bulbs, which indicated that the division of bulbs occurred during the first growing season due to the excess N released from IBDU. The weight of M. armeniacum with IBDU was smaller than that with the silk waste, which suggested that salt damage occurred in the first growing season resulting in the depression of fertilizer efficiency or that the fertilizer efficiency of the silk waste was higher than that of IBDU in the second growing season. These results suggested that silk waste was an efficacious fertilizer in planting under these conditions.

Effects of duration of bulb chilling on dry matter distribution in hydroponically forced tulips

Bulbs of tulip ( Tulipa gesneriana L. ‘Gander’), in which the formation of floral organs had been completed, were chilled at 2°C for 3–30 weeks and then forced hydroponically at 20°C under a 12 h photoperiod with the light at 100 μmol m −2 s −1. The fresh weight and the perianth length of the cut flower highly correlated with the dry weights of shoots and floral organs at anthesis, respectively. The dry weights at planting ( DW p ) of shoots, floral organs and daughter bulbs increased with increasing the duration of bulb chilling at 2°C ( t c ). After a 30-week t c , enlargement of daughter bulbs had already started and their DW p was high. The days from planting to anthesis ( t pa ) decreased hyperbolically with increasing t c . The dry weight at anthesis ( DW a ) of shoots increased with increasing t c up to 12 weeks and then decreased. DW a of floral organs decreased and that of daughter bulbs increased with increasing t c . After a 30-week t c , the DW a values of shoots and floral organs were markedly small and that of daughter bulbs was very large. The dry weights of shoots, floral organs and daughter bulbs increased exponentially after planting, and the relative growth rate during the period from planting to anthesis ( R pa ) in each plant part was calculated. The changes of DW a of each plant part after various t c could be explained by their changes in the growth parameters, i.e., DW p , t pa , and R pa which were shown as functions of t c .

りん茎の低温貯蔵期間と栽培温度が水耕チューリップの生長に及ぼす影響の解析

Bulbs of Tulipa gesneriana L. 'Gander', chilled at 2°C for 12, 18 or 30 weeks were grown hydroponically at 12, 16 or 20°C under a 12-hr photoperiod to force them into growth. With increasing the forcing temperature, the dry matter accumulated in new organs, i.e. shoots and daughter bulbs at anthesis decreased and dry matter remained in mother bulbs increased. In bulbs chilled at 2°C for 30 weeks, more dry matter stored in the mother bulbs was partitioned to the daughter bulbs rather than to the shoots at anthesis, compared to bulbs chilled for 12 or 18 weeks. Irrespective of chilling durations (tc), apparent activation energy (Ea) of reciprocal of days from planting to anthesis (1/tpa), which was calculated by Arrhenius' law, was larger than Ea of relative growth rate (Rpa) of shoots and daughter bulbs. This finding indicates that the change in tpa has greater impact on the final accumulation of dry matter in new organs than that in Rpa of individual organs. The relative values (Ir ; 1 at 20°C of forcing temperature) of tpa and Rpa of shoots and daughter bulbs were calculated for each chilling duration. The change in Ir of tpa and Rpa with forcing temperature was exponential. The results of multiple regression analysis showed that bulb chilling duration has little impact on Ir.

促成水耕チューリップにおけるりん茎の貯蔵温度と期間が乾物分配に及ぼす影響の解析

チューリップ(Tulipa gesneriana L.)'ガンダー'りん茎を6月に入手後20℃で4∿26週間乾燥貯蔵し, 続いて2℃で8週間貯蔵した.また, 入手後のりん茎を20℃で8週間貯蔵し.続いて-2℃, 2℃, 5℃, 9℃の低温で6∿36週間貯蔵した.貯蔵後のりん茎を20℃一定, 12時間日長下で水耕栽培した.新しく生長する器官(シュート, 花器, 内子球)の植付けから開花までの相対生長率を算出した.20℃貯蔵期間は新器官の植付け時乾物重に大きく影響し, 到花日数ならびに相対生長率への影響は小さかった.一方, 低温貯蔵が短期間の場合, -2℃あるいは2℃といったより低い貯蔵温度では, 5℃あるいは9℃といったより高い貯蔵温度と比較して, 到花日数が小さく, 相対生長率が大きくなった.しかし, 低温貯蔵の期間が長期に及ぶと, 植付け時におけるりん茎内の新器官の生長が, 5℃あるいは9℃といったより高い温度での貯蔵において進んでおり, このことが到花日数の短縮をもたらしたと考えられた.長期の低温貯蔵によって, 開花時におけるシュートや花器の乾物重の減少や不開花が観察された.一方, シュートとの養分の競合部位である内子球に分配された乾物が増加した.これは, 2℃, 5℃, 9℃区における植付け時の内子球の肥大あるいは-2℃区における相対生長率の増加に起因すると考えられた.両実験において, 到花日数や新器官の植付け時乾物重, 開花時乾物重, 相対生長率といった生長特性値のほとんどと, 20℃あるいは低温貯蔵期間との関係は非線形回帰で表された.

Growth and flowering of Ornithogalum saundersiae Bak

The growth and flowering of Ornithogalum saundersiae Bak. was studied under field conditions in Kenya. This plant was found to be a perennial syanthous geophyte without a natural dormant period in Kenyan tropical conditions and to form a lateral inflorescence, and thus to grow as a monopodial plant. Number and/or size of bulblets/buds, leaves, inflorescences and total number of nodes in a bulb were found to be determined by the following factors: the size and age (mother or daughter bulbs) of bulb and stage of growth at which bulbs were lifted for subsequent planting. Comparisons of the relative position of each bulb constituent on various sizes of bulbs made it possible to determine the relative age, type and quality of a bulb. After growth and flowering was repeated for some cycles, this plant seemed to form a terminal inflorescence between two vegetative shoots which were found at the bulb apex. This was considered to be the final growth stage of the bulb.

Cytological Examination of Scilla peruviana L. during a 20-month Cycle of Growth and Development

The growth cycle of Scilla peruviana L. involved the development of two generations of daughter bulbs enclosed within each mother bulb. Flower initiation of the primary daughter bulb took place in June as the mother bulb apparently entered dormancy. Floral differentiation was complete by late October, by which time the apical meristem of the secondary daughter bulb had developed for 3 months inside the primary daughter bulb. The complete cycle of ontogenesis, from meristem initiation to flowering, occurred without interruption and required 20 months. Small zones of meristematic cells detected at the bases of bulb scales may be the origin of adventitious bulblets in this species. This detailed cytological study enabled the development of an effective commercial forcing program for S. peruviana.

Ethylene Induction of Flowering and Gel Analysis of Apex Proteins in Dutch Iris 'Telstar'

Nonflowering-sized Dutch iris bulbs 'Telstar' were treated at 20 °C in a flow-through system with ethylene-free air or air containing 10 μL.L-1 of ethylene (C2H4) for 1 or 24 hours. Following the treatment, bulbs were placed in a 10 °C cooler for 5 weeks before planting and subsequently forced in a 20 °C day/18 °C night glasshouse. Results demonstrated that a 24-hour C2H4 treatment induced earlier flowering as well as percent flowering. Flowering responses of bulbs treated with C2H4 for 1 hour were the same as those treated with air. The 24-hour ethylene treatment did not affect the combined fresh weight of the daughter bulb and bulblets but reduced the number of bulblets produced by each. The effects of ethylene on the protein changes in the apex were examined at two time periods: immediately after the treatment and after the cold treatment. Each sample consisted of proteins extracted from three apices. There are significant changes in one-dimensional SDS PAGE protein patterns of bulbs apices after treatment with ethylene. However, the differences are apparent after only 1 hour of ethylene treatment. The cold treatment resulted in minimal further changes in protein patterns.

COMPETITION BETWEEN SPROUT AND DAUGHTER BULBS FOR CARBOHYDRATES IN TULIP AS AFFECTED BY MOTHER BULB SIZE AND CYTOKININS

Planting of large mother bulbs resulted in large tulip flowers, planting of small mother bulbs in small tulip flowers. However, a heavier bulb gave a relatively lighter tulip flower, indicating different mechanisms for the redistribution of fresh weight and dry weight. The possibilities to grow good quality tulips from small sized bulbs were investigated in terms of source sink relationships, for a “splitting” cultivar, cv. Apeldoorn, as well as for a “non-splitting” cultivar, cv. Parade. Over the period between planting and flowering, the recovery percentage of dry matter in generative bulbs depended on the size of the mother bulb, changing from about 70 to 60% for bulb size 14 to 8 respectively. The distribution of dry matter at the moment of flowering also depended on the size of the mother bulb. In small sized (8) bulbs about 85% of dry matter was transported to the tulip flower, in big sized bulbs this percentage was about 40%, resulting in different amounts of dry matter left in the scales. The percentage dry matter transported to the daughter bulbs never exceeded 12% at the moment of flowering. Tulip flowers grown from big sized bulbs also contained a higher percentage dry weight than tulips grown from a small sized mother bulb. Removing scales from a big sized tulip bulb before cold treatment or immediately before planting, resulted in a system comparable to small sized mother bulbs: slightly more dry matter was lost in the period from planting to flowering, a higher percentage of dry matter was transported to the tulip flower, and the tulip flower itself contained a lower percentage of dry weight. Injection of tulip bulbs with benzyladenine (BA) immediately before planting resulted in a higher FW of the tulip flowers. As the DW of the tulips did not increase, this result is due to a higher water uptake. Therefore, the redistribution of DW from source to sink was unaffected by application of BA.

STORAGE METHODS TO MAINTAIN A TULIP COLLECTION

Collections of tulip genotypes are maintained by yearly planting, harvesting and storage of the bulbs. To optimise the maintenance, two methods were examined for their suitability to store bulbs for one or more growing seasons. Method 1: bulbs were stored after flower development at -2 °C. Method 2: bulbs were stored before the start of flower development at -0.5 °C, followed by a temperature regime of 4 weeks 25 °C, 6 weeks 20 °C and 16 weeks 5 °C, for development of sprouts. With the first method, bulbs of ten genotypes could be stored for one growing season without loosing their ability to form daughter bulbs. With the second method, bulbs of three genotypes could be stored for two seasons, without loosing their ability to form daughter bulbs.

Annual Growth and Development of Scilla peruviana

Scilla peruviana is a bulbous plant whose distribution extends from South Africa, into Europe and Asia. It belongs to the family Liliaceae (subclass Monocotyledonae). S. peruviana is an attractive floral species with excellent commercial potential, but it does not produce many bulblets and its multiplication rate is very low. Increasing the multiplication rate, and regulation of its growth and development, cannot be achieved without knowledge of its basic patterns of ontogenesis. We studied the annual growth and development of S. peruviana, from initiation until differentiation, giving special attention to cytological changes at the apical meristem. We also investigated the cytophysiological changes occurring in scales during ontogenesis. Two generations of daughter bulbs are present in each mother bulb. Flowering of the mother bulb coincides with vegetative development of the apical meristem of the primary daughter bulb (March-April). During gradual senescence of leaves and roots of the mother bulb, the apical meristem of the primary daughter bulb undergoes a transition from vegetative to prefloral development (June). Intensive flower organ differentiation occurs in the daughter bulb during the mother bulb's rest period (July–August). Initiation of the apical meristem of the secondary daughter bulb occurs within the primary daughter bulb, which is itself enclosed within the mother bulb (August). The development of the apical meristem of a daughter bulb, from its initiation until flowering, thus occurs without interruption and takes ≈20 months. By modifying external factors such as temperature and growth regulators, we can now control time of flowering and increase the multiplication rate of S. peruviana.

Effect of Ambient Temperature on the Growth and Development of Amaryllis(Hippeastrum hybridum hort.) Bulbs.

How different day/night temperature affect the growth and development of the vegetative and reproductive parts, including the bulbs of amaryllis (Hippeastrum hybridum) plants in growth chambers for two years was investigated. One-year-old, 2-leafed seedlings were transferred to growth chambers set at 17 °/12°C (low, L plot), 24°/17°C (middle, M plot) and 30/24°C (high, H plot) under natural daylength.1. High temperatures (H plot) hastened the unfolding and elongation of leaves, and increased markedly the growth of mother bulb and daughter bulbs, but the plants did not flower.2. In plants exposed to low temperature (L plot), the leaves were the slowest of the three plots to unfold and elongate; the mother bulbs were slow to enlarge but produced the most daughter bulbs. The temperature favored floral development.3. Middle temperature (M plot) educed intermediate vegetative growth and the enlargement of mother and daughter bulbs. This condition was optimum for flower stalk elongation and flowering.Thus, comparing the responses of amaryllis grown under low, middle, and high day/night temperatures, high temperature favored promotion of mother bulb enlargement, but the moderate and low temperatures were optimum for bulb and flower production.

DETECTION OF TOSPOVIRUSES IN BULBOUS CROPS AND TRANSMISSIBILITY BY VEGETATIVE PROPAGATION.

In dahlia visual selection on tomato spotted wilt virus (TSWV) is only possible to a limited extent. The unequal distribution of the virus in various plant parts during the growing and storage period caused problems in the development of a reliable test protocol. A serological test on tubers appeared to be the best: the tubers have to be stored for at least 1 month at 9°C and samples have to consist of at least three roots per tuber. 40-90% of the cuttings from TSWV-infected dahlia tubers appeared to be infected. Symptoms of TSWV in both gladiolus and iris cannot be distinguished from those caused by Impatiens necrotic spot virus (INSV). In iris a third (putative) tospovirus was detected, which is called iris yellow spot virus. In progeny-plants from infected iris and gladiolus no tospoviruses were detected. In Hippeastrum, Amaryllis and Nerine TSWV was detected in symptom-bearing leaves and also in the tunics connected with these leaves, but less frequent in other parts of the bulbs. This might explain the curing of the main bulbs after some years and the limited transmission of TSWV to the daughter bulbs.

The Effect of Irradiance, Defoliation, and Bulb Size on Flowering of Nerine bowdenii W. Watson (Amaryllidaceae)

Large Nerine bowdenii bulbs (>14 cm in circumference) were exposed to low ligbt intensities for different periods during two successive growing seasons. The flowering percentage and number of florets in the current season's inflorescence were recorded at anthesis. Small and large bulbs were subjected to continual defoliation starting at different times during the growing season. Bulbs were dissected at planting (26 Sept. 1992) and on 12 Jan. 1993 (nondefoliated control bulbs) to determine growth and developmental stage. At anthesis, inflorescences were harvested and the florets per inflorescence were counted. After anthesis in the fall, all bulbs were dissected and the following variables recorded: 1) percentage flowering, quiescence, or abortion of the current season's inflorescence; 2) developmental stage of quiescent inflorescences; 3) number of florets in the outermost inflorescence; 4) developmental stage of the innermost inflorescence; 5) number of leaves or leaf bases in each growth unit; 6) number of daughter bulbs; and 7) dry weight of new leaf bases. There were three reasons for nonflowering of the bulbs, viz., failure to initiate an inflorescence, inflorescences remaining quiescent, and inflorescence abortion. Individual florets that had not reached stage “Late G” (gynoecium elongated, carpels fused) at the start of rapid inflorescence elongation aborted. The more florets that aborted, the greater the probability that the entire inflorescence aborted. The inflorescence was more vulnerable to stress during the first half of the growing season due to its relatively weak position in the hierarchy of sinks within the bulb.

自生ササユリ球根の発育とりん片培養による子球形成との関係

Experiments were conducted to clarify the relationship between seasonal changes in bulb growth of Lilium japonicum Thunb. in the field under natural conditions and bulblet formation on in-vitro cultured scales.When scales are detached from a bulb, vestiges of stems from past years are detectable on the basal plate. The year, the scales were formed, was identified by the positions of the residual stems on the basal plate. Each year, a new daughter bulb, consisting of about 7 scales, which develops within the mother bulb and the growth of the new shoot, which occurs between April and July, consume 3 to 4 outer-scales of the mother bulb.The bulbs were collected on 10 March, 1 July and 14 October, and their scales cultured for 13 weeks. The rate of bulblet formation on the scales collected on 10 March was fastest. The formation rate and fresh weight gain of the regenerated bulblets, which formed on the outer scales, were faster than those on the inner scales.We conclude that to regenerate bulblets by in-vitro scale culture, early spring is the optimum time to collect the bulbs.

Comparative Growth and Development of Nerine bowdenii W. Watson: Bulbs in Situ versus Replanted

Flowering-size Nerine bowdenii bulbs were sampled from a commercial planting at 2-week intervals from 13 Aug. 1991 to 14 June 1992. They were dissected, and the following variables were recorded: 1) number and dry weight of fully sheathing leaf bases or leaves of each growth unit, 2) length and dry weight of foliage leaves, 3) fresh weight of outermost inflorescence, and 4) dry weight of daughter bulbs. Bulb organs that served as sinks and sources changed as the bulb progressed in its growth and developmental cycle. Before the new foliage provided photosynthates, growth depended on reserves deposited and stored in leaf bases during the preceding seasons. Reserves were used for the development of new leaves (foliage and bases), roots, and daughter bulb enlargement. Once the foliage became the photosynthate source, reserves were stored in old and new leaf bases. The inflorescence became the major sink when elongation of the scape initiated. Thereafter, daughter bulbs became the dominant sinks, receiving photosynthates from the senescence foliage and the reserves stored in leaf bases. The decrease in dry weight of the leaf bases was prominent in bulbs that remained in situ.

Respiration of bulb scale fragments of tulip after storage at 5°C

Tulip bulbs need a period of low temperature prior to planting in order to develop a flower stalk of sufficient length and a flower of good quality. The response of the respiration of bulb scale tissue in relation to a cold treatment (5°C) was investigated. Transfer of bulbs to 5°C resulted in a rise of the respiration of the tissue. This respiratory adjustment reduces the decrease in enzymatic activities due to the lower temperatures and enables a continuation of all physiological processes and growth at a relatively high rate. During prolonged storage at 5°C the respiratory capacity of bulb scale tissue gradually returned to the original lower level. Apparently, the need for increased respiratory activity was only temporary. When bulbs were transferred back to 17°C after a 5°C treatment of variable length, the reaction of bulb scale tissue respiration differed early and late in the storage season. Early in the season (November) when shoot development is optimal, no clear increase in respiration occurs. Late in the season (in January) transfer to 17°C resulted in a large increase in respiration. These bulbs show no increased shoot growth, but develop daughter bulbs. The nature of these two different reactions is discussed amongst others in relation to changes in ethylene production by the bulbs.

Underground Plant Movement

AbstractA special preparation method makes it possible to observe the underground bulb movement of Nothoscordum. This movement is effected by contractile roots. Straight ahead movement, which seems to be typical for many bulbous plants, is only exceptionally seen in Nothoscordum. Bulb movement in Nothoscordum occurs by tilting and twisting, effected by the pulling force of contractile roots on one side of the bulb. Also, vegetative dispersal of lateral bulbs (daughter bulbs) caused by the pulling force of contractile roots can be documented. Finally, starting from the seedling, the overall bulb movement can be demonstrated, showing how the plant penetrates the substratum thus reaching the optimum depth.

GROWTH RETARDATION OF NARCISUS TAZETTA DURING FORCIN

Bulbs of the Chinese Sacred Lily (Narcissus tazetta) are forced in water about 28 days before Chinese New Year. Excessive leaf and scape length may necessitate tying to render the plants presentable. No. 1 bulbs which had been cleaned and placed in water for 2 days were treated with 10 ppm ancymidol, 50 ppm paclobutrazol, 25 ppm uniconzole, 10 ppm flurprimidol, or 100 ppm ethephon. At 70% of control plant height, ethephon-treated plants were shortest, and flowering was not delayed. Daughter bulbs were soaked in 50 ppm flurprimidol to determine the most effective stage at which to treat. Soaking the dry bulbs for 1 hour at 36°C was most effective (58% of control), but delayed flowering more than a week. Soaking the bulbs for one hour when emerging roots were @ 0.5 cm long was also effective (65% of control). At 11 days of forcing when emerging leaves were 4 - 6 cm long, the entangled root sytems wer soaked in the retardant which was then drained off. This treatment achieved 74% of control growth. Scap lengths in all flurprimidol treatments were 60-65% of the foliage length compared to 82% for the controls.

Asexual propagation of variegated Lilium longiflorum ‘Chotaro’

Scale propagation of variegated Lilium longiflorum cultivar ‘Chotaro’ produced more than 93% of variegated plants from middle scales (MS), inner scales (IS) and innermost scales (IMS). Outer scales (OS) produced a lower percentage of variegated plants and a higher percentage of non-variegated (green) plants than the other scales. A total of 875 typical variegated plants was obtained from 620 scales detached from 10 parent bulbs. Parent bulbs, of which the basal plate was wounded with a nail, produced three times more daughter bulbs than the controls. All these daughter bulbs were variegated.

Whole-plant Response of Easter Lilies to Ancymidol and Uniconazole

Abstract All growth retardant treatments (ancymidol, 50 mg·liter−1, one or two sprays; uniconazole, 5, 10, or 15 mg·liter−1, one or two sprays; 20 mg·liter−1, one spray) reduced Easter lily (Lilium longiflorum Thunb.) plant heights when compared to controls. Plant heights decreased linearly with increasing concentration of uniconazole for both one- and two-spray treatments. High concentrations of uniconazole delayed anthesis; ancymidol treatments did not. Individual corolla length was not affected by treatments. Treatments did not affect daughter bulb depletion or new daughter bulb growth. Total leaf area and leaf dry weight decreased as uniconazole concentration increased; ancymidol treatments did not affect leaf area, but did reduce leaf dry weight. Leaf total soluble carbohydrate decreased with increasing concentration of uniconazole. Chemical names used: α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidine-methanol (ancymidol); (E)-1-(p-chlorophenyI)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol (uniconazole).