hand-pollination crossing (Orobanchaceae)

Knowledge graph centered on hand-pollination crossing (Orobanchaceae) with 54 nodes and 165 connections. Top connected: Hummingbird, Ipomopsis, Delphinium, I. aggregata, Ipomopsis aggregata.

Method synopsis

Controlled laboratory assay using prepared stigmas on growth medium to test pollen germination and tube growth across species boundaries. Stigmas are prepared from unopened buds, treated with pure pollen loads, and incubated under controlled conditions to observe tube growth.

Synthesized from method descriptions across 2 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Phylogeny does not predict the outcome of heterospecific pollen–pistil interactions in a species-rich alpine plant community (2025), American Journal of Botany. Implementations in other papers (listed below) may differ.

1. Collect unopened flower buds for stigma preparation
   Collected unopened flower buds that were close to opening from naturally pollinated flowers using a paintbrush. Buds were collected, dissected, and plated the same day to ensure flower freshness.
   Quantities: Multiple buds collected per species for each batch, exact number varies by availabilityDuration: Same day collection and processingConditions: Early-stage buds with nonreceptive stigmas that have yet to develop species recognition mechanisms
   Equipment: paintbrush, dissection tools
2. Prepare stigmas for pollen tube growth assay
   Tested stigma receptivity using nitrogen peroxide and Kearns and Inouye 1993 method applied to five buds from each batch. If all five stigmas were determined to be receptive, then buds of that size were used for experimentation. Carefully removed anthers to use as pollen treatments in the experiment, then removed the ovary to be used as an attractant and cut the style such that it was no more than 2 mm.
   Quantities: 5 buds tested per batch for receptivity, 2 mm maximum style lengthDuration: Processing completed within 24 hours of pollinationConditions: Stored at 4°C, completely covered, placed on pollen tube growth medium
   Equipment: nitrogen peroxide, dissection tools, pollen tube growth medium
3. Apply pollen treatments to prepared stigmas

Typical Equipment

• paintbrush
• dissection tools
• nitrogen peroxide
• pollen tube growth medium
• petri dishes
• growth chamber
• dissecting microscope

Output Measurements

• pollen tube germination success
• pollen tube growth through stigma

Papers Using This Protocol (2)

Species Studied With This Protocol