Sap Yield Research Articles

Photosynthetic Assimilation, Carbohydrates in Vegetative Organs and Carbon Removal in Nut-Producing and Sap-Producing Coconut Palms

The net assimilation rate, carbohydrate content in leaf and trunk tissues and quantum of carbon removed in sap-producing (SP) and nut-producing (NP) coconut palms were compared. The correlations between sap (toddy) yields of SP palms, and their leaf and trunk carbohydrate content; net assimilation rate; and the pre-tapping phase nut yields, were investigated as possible criteria for selecting coconut palms with potential for high toddy yields. Thirty-five-year-old coconut palms of the Tall variety (Cocos nucifera L., var. typica), at Bandirippuwa Estate, Lunuwila, Sri Lanka were used for the study. Total soluble sugar content (TSS) in leaf and trunk tissues was higher (62-73 mg g dw-1) than their starch content (24-41 mg g dw-1) in both SP and NP palms. In SP palms, TSS of leaf tissue was higher, and trunk tissue was lower, than in NP palms. The total carbohydrate (TC) content in the trunk was generally higher than in leaves of both SP and NP palms. In SP palms, the ratio of TSS : starch was higher in leaves, and lower in the trunk, than in NP palms. Net assimilation rates and carbon removal by the produce (nut or sap) was similar in NP and SP palms. There was no significant correlation between sap yields and TSS and starch contents of leaf or trunk tissues of palms, before and during tapping; and the nut yields before; and the NAR during tapping. These parameters are therefore not of predictive value for selecting coconut palms for high sap yield. Key words: Cocos nucifera L., coconut, inflorescence sap, toddy, soluble sugars, starch, physiology, assimilate storage doi: 10.4038/cocos.v18i0.988 COCOS (2007), 18

ETHREL STIMULATION OF INFLORESCENCE SAP FLOW IN TAPPED COCONUT (COCOS NUCIFERA) PALMS

The effect of Ethrel on the yield and sugar content of coconut (Cocos nucifera) inflorescence sap and sustainability of productivity was investigated on forty-year-old tall coconut palms (var. typica) at Bandirippuwa Estate, Lunuwila, Sri Lanka. Ethrel was applied at a concentration of 2.5% and the volume and sugar content of the sap were measured. Application of Ethrel consistently increased the yield per day, yield per spadix, yield per palm per annum and sugar content in the sap for a period of four years. The removal of carbon, nitrogen, phosphorus, potassium and magnesium with the sap was greater from Ethrel-treated than from untreated palms, and this was attributed mainly to the enhanced sap yields and sugar concentrations.

Soil and leaf analysis of fertilized sugar maple stands after ice storm damage

Lime and/or PK fertilizers were applied as remedial soil treatments to 33 sugar maple (Acer saccharum Marsh.) woodlots established on a broad range of sites in eastern Ontario. All woodlots were actively used for maple syrup production and had suffered varying degrees of crown damage as a result of the 1998 ice storm. Soil and foliar samples were collected one and three growing seasons after treatment to assess changes in soil fertility and nutrition of these stands. Except for Ca from liming, the treatments significantly increased soil supply of added elements (P, K, Ca or Mg) as measured by standard laboratory methods. These effects may be relatively short-lived, as soil nutrient levels on treatment plots had started to decline by the end of the third season after treatment. Liming alleviated acidity on acid soils, but pH of neutral calcareous soils was unaffected, thus allaying initial concerns that liming may be "toxic" on these soils. The liming response was rapid, and persisted into the third growing season. Nutrient responses in soils were reflected in foliar analyses. Leaf P, K, Ca, and Mg were significantly raised when added as soil amendments. The results show that first-season nutrient responses to fertilizer additions are sensitive indicators of treatment effects on soil and foliage of sugar maple in the region. Initial growth assessments suggest a 15–22% basal area increment to P and K applications; however, it is not known if these early treatment effects will translate into long-term tree growth and sap yield responses. Key words: Acer saccharum, phosphorous and potassium fertilization, liming, soil tests, foliar analysis, soil acidity

USE OF PETIOLAR SAP NITRATE FOR ASSESSING NITROGEN STATUS OF IRRIGATED BRUSSELS SPROUT CROPS

ABSTRACT Four field experiments were carried out during 1992/93 (sites 1 and 2) and 1993/94 (sites 3 and 4) to assess the effects of nitrogen (N), at rates up to 600 kg N ha−1 on sap nitrate concentrations in petioles of the youngest fully expanded leaves (P-YFEL) of Brussels sprouts (Brassica oleracea L. var. gemmifera). The experiments were located in commercial plantings in the Mount Lofty Ranges of South Australia. Plant samples were collected at 2–4 week intervals from 4 to 28 weeks after the plants were transplanted. Temporal variation and the effect on sap nitrate concentration of sampling leaves next in age to the index leaf (YFEL−1 to YFEL+2), were also studied. Nitrate concentrations in the sap of P-YFEL showed poor sensitivity to variations in side-dressed N fertilizer and the magnitude of the changes varied between sites and sampling time. For example, at 12 weeks after transplanting, sap nitrate concentrations varied by less than 2,000 mg L−1 over the range of N applied. Nitrate concentrations in petioles also varied with the age of the leaf sampled. Nitrate concentrations in petioles sampled at 4, 6, 8, and 10 weeks after transplanting increased with leaf age. Linear and quadratic models were used to study the relationships between sap nitrate concentration in P-YFEL sampled during the period 4 to 24 weeks after transplanting and yield response to applied N. Significant relationships were only found at site 2, 8 weeks after transplanting, R2=0.98; site 3 at 18 weeks, R2=0.87 and site 4 at 8 and 10 weeks, R2=0.93 and 0.87, respectively. Based on lack of sensitivity (as indicated by the narrow range in petiolar sap nitrate concentrations in response to variations in N supply), temporal variation (changes in petiolar sap nitrate concentrations during the season) and the lack of consistent relationships between sap nitrate concentrations and yield response, we concluded that sap nitrate concentration is not a useful indicator of plant N status and yield response of Brussels sprouts.

Productivity and water relations of field-grown cashew: a comparison of sprinkler and drip irrigation

Cashew is an emerging crop in the seasonally ‘wet–dry’ tropical regions of northern Australia. In North Queensland flowering and fruiting of cashew coincides with the dry season (May–November). During this period growers sprinkler irrigate at 500 L/tree.week. A 3-year (1996–98) experiment compared this strategy with alternatives, including no irrigation or drip irrigation in which 115 or 230 L/tree.week was applied by drippers placed near the tree trunk and near the canopy drip line throughout the dry season. Measurements of soil water to 1.3 m, leaf gas exchange, chlorophyll fluorescence, tree sap flow and yield were made. Data collected in the first 2 years showed that the water requirement of the trees increased progressively as the crop load and evaporative demand increased during the dry season. During the final year of the study, additional sprinkler and drip treatments, in which water applications were progressively increased during the dry season, were introduced. The productivity of cashew in this experiment was strongly influenced by irrigation treatments, ranging (over all years) from 42 to 160 g nut/m 2 canopy surface area. Depletion of plant-available water in the root zone was associated with a reduction in photosynthesis mediated by partial stomatal closure. These effects of soil drying were evident in all irrigated treatments during the mid and late stages of the dry season but were more severe in treatments receiving the least water. When irrigation was withheld until the mid-stage of the dry season the trees had similar yields to those that were irrigated throughout, emphasising the importance of providing adequate irrigation between nut set and harvest. When rainfall from January to September in each year of the study was taken into account, there was a strong linear relationship between nut yield and water applied (rainfall + irrigation), with each extra kilolitre of water applied resulting in about 6 extra g nut/m 2 canopy surface area. This linear relationship was based on water application in the range 25–50 kL per season. It is possible that if the seasonal water application had exceeded 50 kL the marginal response to extra water may have diminished. Using drippers was slightly more efficient than sprinklers, with drip-irrigated trees requiring about 5% less water applied to achieve a given nut yield. In years when rainfall is average, and subject to other economic factors, growers in North Queensland should aim to irrigate about 500 L/tree.week. In years of low rainfall between January and September it is likely that yield will be improved by applying more irrigation water; high rainfall during these months of the year may reduce the irrigation requirement. In all cases growers should be careful to accurately monitor water applications, particularly when the total (from rainfall + irrigation) exceeds 40 kL/tree for the season.

Soybean (Glycine max), common cocklebur (Xanthium strumarium), and sicklepod (Senna obtusifolia) sap flow in interspecific competition

Two field experiments were conducted to examine the competitive effect of common cocklebur and sicklepod in soybean. Factors examined included sap flow of both the weed and the crop, as well as the traditional parameters of weed and crop growth and crop yield. The intent was to determine to what extent competitive effects could be attributed to differential water utilization. In the first study, soybean planted at 20 plants m−1row was infested with either sicklepod at 10 plants m−1row or common cocklebur at two plants m−1row. Sicklepod reduced soybean sap flow and yield 53 and 49%, respectively. Common cocklebur reduced soybean sap flow and yield 31 and 38%, respectively. Within a weed species, weed-induced yield and sap flow reductions were comparable, indicating that water deprivation was the primary detriment that these weeds inflicted on soybean. Individual common cocklebur plants were 3.9 times more competitive than sicklepod with respect to reducing soybean yield. However, sap flow of individual common cocklebur plants was only 1.4 times more than that of sicklepod, indicating that water deprivation was not the only causal factor in weed-crop competition. In the second experiment, sicklepod was planted in soybean (fixed density) and clipped to either half the height, same height as soybean, or left unclipped, in an attempt to simulate herbicide-induced stunting. Clipping sicklepod had a positive effect on soybean sap flow and yield. Thus, the benefits of reduced weed competition were achieved without killing sicklepod.

Maple syrup from Manitoba maple (Acer negundo L.) on the Canadian prairies

Manitoba maple (Acer negundo L.), which occurs naturally throughout Saskatchewan and Manitoba and has been planted extensively in prairie shelterbelts, is now beginning to be used to produce maple syrup on a small commercial scale. The product is a light-coloured syrup which has been judged to have a distinctly pleasant flavour. The product is presently sold locally with an emphasis on its distinctiveness of flavour and its origin on the prairies. Studies completed at Indian Head, Saskatchewan show that sap sugar content is slightly less than that of the sugar maple and that its sap flow volume is considerably lower. A three year mean sap yield of 9.8 L per tap resulted in a syrup yield of 0.23 L per tap. This is about one quarter to one half of that in a sugar maple. Key words: Maple syrup, Manitoba maple, prairie shelterbelts

Effets des coupes d'éclaircie et des variations climatiques interannuelles sur la production et la teneur en sucre de la sève d'une érablière

A study was initiated in 1975 on a sugar maple (Acersaccharum Marsh.) stand of the Station forestière de Duchesnay (46°57′N, 71°39′W) to determine the effect of thinning on sap production of sugar maple. From 1975 to 1989, spring sap flow and sugar concentration were measured in 58 sample plots distributed in five blocks within which three intensities of thinning (0, 22, and 35% of the initial basal area) were applied. Thinning intensities only accounted for a small part of the variation in sap volume per tap and sap sugar concentration. However, more than 60% of the variation of these two sap characteristics was related to year-to-year variations. This suggests that sap yield and sap sugar concentration were largely controlled by the different climatic conditions that occurred during these years. Hence, sap yield was strongly correlated with the number of days characterized by temperature fluctuations around 0 °C during springtime and by winter precipitation. Sap sugar concentration was also correlated to the number of days with temperature fluctuating around 0 °C during springtime but all other tested meteorological variables failed to improve this relationship. While thinning intensities did not affect sap yield per tap and sugar concentration, sugar yield per hectare could be improved by thinning over the long term since it increased the potential number of taps per hectare.

SEQUENTIAL COCONUT TODDY (SAP) AND NUT PRODUCTION

Production schemes, namely sequential, production of coconut sap/toddy and nuts in same spathe/spadix (SCTNP); nut production only (NP) and toddy production only (CTWS) were tested at PCA Davao Research Center, using Laguna Tall for a period of three years. Palms under the CTWS and the SCTNP had more coconut sap yield over the periodic tapping and nut production (3 or 6 month’s duration) in three years of tapping operation. Annual toddy yield in the SCTNP did not differ significantly with the CTWS during the first and third years of tapping. Generally nut yield of palms with SCTNP was about 50% lower than control palms (NP). As compared to palms under NP, copra yield per palm with SCTNP was likewise around 50% lower. Leaf nutrient concentrations of N, P, K. Ca. Mg, Na, Cl, S and B were not significantly affected by toddy‑lapping under the four production schemes.
 
 Results clearly showed that the sequential coconut toddy and nut production (SCTNP) is strongly feasible and economically viable to supply both toddy and nuts as farm products by small scale coconut farmers. Compared to the traditional practice of producing nut alone (P 7,500.00 per ha average annual income), SCTNP provides an average net income of P 71,000.00 per ha (P 520.00 per tree), annually.

Income, sap yield and effects of sap tapping on palms in south-eastern Africa

The small size and yield of Hyphaene coriacea and Phoenix reclinata palms in south-eastern Africa makes palm wine tapping a labour-intensive activity providing a subsistence income. Despite these disadvantages, tapping and sale of fermented Hyphaene coriacea and Phoenix reclinata palm sap, together with pastoralism and gathering of wild fruits are important uses of the palmveld. During the period November 1981 – October 1982, a single representative palm wine tapper tapped 712 palms (902 stems), producing 4 846 litres palm wine. Successive groups of tapped palms showed a characteristic rise and fall in sap yields. The sustainable use and improved economic returns from this resource are discussed in relation to tapping technique. Altered tapping technique would allow recovery of tapped stems and a shift towards larger size classes of higher yielding palms. At present this is not possible due to the complications of communal land ownership and multiple use of the palmveld. Omdat die palms Hyphaene coriacea en Phoenix reclinata in suidoostelike Afrika nie baie groot word nie en ’n lae opbrengs lewer, is die tap van palmwyn ’n arbeidsintensiewe aktiwiteit wat ’n bestaansinkomste beskaf. Ondanks hierdie nadele, is die tap en verkoop van gefermenteerde sap van die twee palmspesies, tesame met veeboerdery en die pluk van veldvrugte, belangrike gebruike van die palmveld. Gedurende die tydperk November 1981 – October 1982 het een verteenwoordige palmwyntapper 712 palms (902 stamme) getap en 4 846 liter palmwyn geproduseer. Opeenvolgende groepe getapte palms het ’n kenmerkende skommeling in sapopbrengste getoon. Die hernubare benutting en verbeterde ekonomiese opbrengs uit hierdie hulpbron word met betrekking tot taptegniek bespreek. ’n Gewysigde taptegniek sou die herstel van getapte stamme en ’n omskakeling na groter palms met ’n hoër opbrengs tot gevolg hê. Weens die ingewikkeldheid van gemeenskaplike grondbesit en verskeidenheid gebruike vaarvoor die palmveld benut word, is dit tans egter nie moontlik nie.

Sap yields, sugar content, and soluble carbohydrates of saps and syrups of some Canadian birch and maple species

During the spring of 1984 and 1985, white birch (Betulapapyrifera Marsh), sweet birch (B. lenta L), and yellow birch (B. alleghaniensis Britt.) were tapped to determine sap yields and syrup characteristics. These properties were compared with sap yields and syrup produced from sugar maple (Acersaccharum Marsh) and red maple (A. rubrum L). The sap flow seasons were as follows: white birch, 23 days (April 7–29, 1984) and 29 days (April 5 – May 3, 1985); sweet birch, 26 days (1984); yellow birch, 25 days (1985). The sap flow season for the maple species was much earlier than the birch species. Maple sap flow seasons were as follows: sugar maple, 16 days (March 28 – April 12, 1984) and 45 days (March 10 – April 23, 1985); red maple, 44 days (March 11 – April 23, 1985). Sap yields were as follows: white birch, 80.5 L in 1984 (1.0% sap) 51.0 L in 1985 (1.0% sap); sweet birch, 48.0 L in 1984 (0.5% sap); yellow birch, 28.4 L in 1985 (0.5% sap); red maple, 30.6 L in 1985 (2.3% sap); sugar maple, 53.5 L in 1985 (4.5% sap). Sap analyses showed the average total carbohydrate content of all birch saps and all maple saps was 9.2 and 24.5 g/L, respectively. The average sugar contents of the syrups from the birch saps and the maple saps were 302 and 711 g/L, respectively. The average pH of birch and maple saps were similar but the average pH of the syrups obtained from the birch saps was substantially lower than that of the syrups obtained from the maple saps.

Tapping practices and SAP yields of the NIPA palm ( NIPA Fruticans) in Papua New Guinea

Methods of tapping the nipa palm ( Nipa fruticans Wurmb.) were developed in the course of a 3-year study conducted in seven villages in the Baimuru district of the Gulf Province of Papua New Guinea. The experimental sites were located about 1.5–23 km from the sea. Their plant density varied from 4700 to 2400 palms per ha and the mean height of the plants was nearly 13 m. Five pre-treatment patterns were tested. Once-a-week treatment, maintained for 12 weeks, yielded an average of 155 ml of sap/24 h/palm for one month, whereas 3–5-times-a-week treatment, for 5–12 weeks, yielded an average of 1300 ml of sap. The duration of treatment depended on the state of development of the flower stalk. The pre-treatment pattern chosen as the standard was to bend the stalk 12 times in one direction, to pat with the hands the length of the stalk backwards and forwards 64 times, and to give the base four kicks; this was repeated four times a week. In the course of the 3-year study it was found that the average sugar content of fresh nipa sap is rather high, about 16.4% w/v, as compared with, for example, about 12% w/v of sugar cane. The results of the present study are discussed with reference to producing fuel alcohol from the Papua New Guinea nipa palm.

Harvestable energy from the coconut palm

The harvestable energy from the coconut palm is in the form of husks, shells and oil from the nuts and the leaf petioles with a regular monthly production of a bunch of nuts and one leaf. From the known energy content of the husks, nut shells and petioles, the number of palm trees required to provide the total energy for domestic cooking at wood equivalent to 1–3 kg firewood per day ranges from 5–14 for husks, shells and petioles, or 15–47 if the material is first converted to charcoal. In order to provide diesel fuel containing 10% coconut oil and cope with the annual increase in such a demand, the coconut crop would have to increase at the rate of 1 nut per bunch per month from 3–11 nuts to 12 nuts over the next 8 years. Highest coconut sap yield in ethanol terms, amounts to 109 MJ/month per palm which equals the oil in a 20-nut fruit bunch, thus indicating possible greater energy harvest from coconut sap than from coconut oil.

MICROORGANISMS FROM OIL PALM TREE (Elaeis guineensis) TAP HOLES

ABSTRACTSIn the study of microorganisms from oil palm tree (Elaeis guineensis) tap holes, 12 yeasts, 18 bacteria and 6 mould species were isolated. On the average half of these microfloral species were also cultured from the palm sap obtained from the tap holes. Observations of microfloral population changes during the period of tapping indicate that sap yield began to fall as soon as bacteria and yeast populations each reached 108 per gram of tissue.

Relation of Sap and Sugar Yields to Physical Characteristics of Sugar Maple Trees

Relation of Sap and Sugar Yields to Physical Characteristics of Sugar Maple Trees

Chemical Analysis of Sugar Maple Sap and Foliage as Related to Sap and Sugar Yields

Chemical Analysis of Sugar Maple Sap and Foliage as Related to Sap and Sugar Yields

Effect of N, P, and K Fertilization on Yield and Sugar Content of Sap of Sugar Maple Trees

AbstractSap yield, sap sugar concentration, and sugar yield data from sugar maple trees collected over 3 years revealed great intra‐ and interseasonal variations. The effect of N, P, and K fertilizers, applied singly and in combination, affected the yield of sugar by affecting sap yield and/or sap sugar concentration. The combination fertilizer depressed sugar yield the first sap flow season after treatment and increased this yield in the second season. The N or K fertilizer resulted in little change in sugar yield over the control trees while P fertilizer produced a significant effect on sap sugar concentration, thus affecting sugar yield.

The root sap of birch on a podzol

Root sap analyses were made on birch trees growing in a strongly podzolised heath soil. In the early summer the concentration of calcium and phosphorus appears to vary with the quantity of sap produced, and is independent of root environment. Later in the summer, however, this relationship no longer holds; there now being a connection between rooting zone and nutrient concentration. Roots reaching theC horizon absorb greater quantities of bases, whilst the superficial roots show higher concentrations of phosphorus and ammoniacal nitrogen. Throughout the season potassium uptake remains practically independent of both sap yield and rooting zone. In these soils young pine trees do not penetrate to the subsoil, but a comparison of sap analyses from surface roots of pine and birch shows that birch sap is richer in most nutrients. This, together with the ability of the birch to exploit the subsoil, may be a contributory factor to the soil improving properties of a birch crop.

Influence of Weather Conditions on Sap and Latex Flows

IN NATURE of April 5 appeared a letter by Mr. Folkard under the heading “The Bleeding of Cut Trees in Spring”. Prof. Priestley's remarks on that letter in the same issue bring out points which are of particular interest to me. Some years ago I carried out work on sugar producing palms, during the course of which I made careful measurements of the yields of sap from the cut stems of a number of wild date palms (Phönyx sylvestris) throughout the cold weather. Daily records were also kept of the maximum and minimum air temperatures and the sugar content of the sap was determined. The air temperature exercises a very marked effect on the yield of sap. A rise in temperature is always followed by a falling off in yield, whereas a fall in temperature is always followed by a rapid increase in yield. Moreover, the coldest months of the year are the best from the point of view of sap yield. During these experiments the maximum day temperatures ranged from 71° to 83° F., and the minimum night temperatures from 46° to 66° F. Cloudy nights have an adverse effect on sap yield and on its quality. Newlands (“Handbook for Sugar Planters”) also records that in the case of the maple tree the best yields of sap are obtained during cold clear nights following bright warm days.